erbitux

Immunotherapies gaining traction in head and neck cancers

Source: www.targetedonc.com
Author: Greg Kennelty

An explosion of immunotherapies is on the horizon for patients with metastatic head and neck cancer, specifically as phase III trials begin to report findings for PD-1 inhibitors. This upcoming wave of new therapies places importance on understanding optimal treatment settings and adverse events associated with these therapies.

In late January, the phase III CheckMate-141 trial investigating the anti–PD-1 agent nivolumab was stopped early, due to a substantial improvement in the primary endpoint of overall survival (OS). The drug was put up against the investigator’s choice of cetuximab (Erbitux), methotrexate, or docetaxel following progression on a platinum-based therapy.

At this time, data from the study have not yet been released but are being prepared for future presentation. Findings from the study are being discussed with the FDA and other health authorities.

In addition to nivolumab, the PD-1 inhibitor pembrolizumab (Keytruda) demonstrated encouraging activity in patients with with advanced PD-L1–positive esophageal carcinoma during the phase Ib KEYNOTE-028 study. Additionally, the agent was effective for patients with squamous cell carcinoma of the head and neck in the phase I KEYNOTE-012 study.

In the head and neck cancer population, the objective response rate with pembrolizumab was 24.8% in 117 evaluable patients. Tumor shrinkage was experienced by 56% of patients and another 25% had stable disease. The response rate seen with pembrolizumab was similar, regardless of HPV infection status. In those with HPV-positive disease, the ORR was 20.6% compared with 27.2% in the negative group.

To gain further insight, Targeted Oncology spoke with head and neck cancer expert Barbara Burtness, MD, professor of Medicine (Medical Oncology), Clinical Research Program Leader, Head and Neck Cancers Program, co-director, Developmental Therapeutics Research Program, Yale Cancer Center.

TARGETED ONCOLOGY: Can you give us an overview of where immunotherapy is currently in head and neck cancer?

BURTNESS: The first trials for immunotherapy in head and neck cancer began two or three years ago and we now have sufficient reason to believe that these therapies are going to be active in the cancer. For example, there is the KEYNOTE-012 trial, which was a trial of pembrolizumab given to an expansion cohort of either HPV-positive or HPV-negative head and neck cancer. The response rate there was about 25%.

There is some reason to believe that if either PD-L1 or PD-L2 are expressed, that that would predict for a higher response rate. There are now phase III trials going forward for both platinum-refractory disease and for first-line patients looking at pembrolizumab compared with chemotherapy.

There are also data with MEDI4736, which if a patient is expressing PD-L1, appears to have a pretty high response rate of about 50% in a small group of patients. There are currently ongoing trials looking at the combination of MEDI4736 with tremelimumab, though we don’t have any data on that just yet.

Then there are novel strategies people have for trying integrate immunotherapy with standard treatment. We have some reason to believe that when head and neck cancer is treated with radiation there is upregulation in tumor-infiltrating lymphocytes and PD-L1. There are trials now moving forward that are integrating immune checkpoint inhibitors together with chemoradiation, or taking patients who have completed their chemoradiation but have persistent disease and exposing them to pembrolizumab in that setting.

The last thing is there is some evidence that siltuximab can upregulate a co-stimulatory molecule, CD137. There are some trials looking at co-targeting EGFR and CD137.

TARGETED ONCOLOGY: What are the side effects in immunotherapy?

BURTNESS: The one thing community oncologists should be aware of is toxicities. As these drugs roll out, these toxicities that will be present are a lot different to manage than the usual cytotoxic agent toxicities. There are a lot of unusual or unexpected side effects that are autoimmune in nature.

The most common toxicity is fatigue. Across all the patients with head and neck cancer who received pembrolizumab, about 17% of them had grade 3 or 4 toxicities. This is a lot easier to tolerate than chemotherapy or chemoradiation. The other things that you might look for are pneumonitis, nephritis, pancreatitis with diabetic symptoms, thyroiditis, and a variety of unusual autoimmune side effects.

TARGETED ONCOLOGY: What do you see as the overall potential for immunotherapy in head and neck cancer?

BURTNESS: Everybody with biomarker expression of either the ligands or the targets in this pathway is likely to be exposed to these drugs in the future. The challenge for us is going to be to figure out, for those patients who are not PD-L1 expressing or who don’t have tumor-infiltrating lymphocytes, other ways that we can prime patients for immunotherapy with our standard treatments. It’s speculative – it’s not something that people are doing in clinics now, but the first trials of those approaches are starting.

There is also ADXS11-001 that is fused to the E7 oncogene from HPV. The idea is that that would increase antigenic presentation and then the immune checkpoint inhibitor could potentially be more effective. That treatment is still in phase I.

February, 2016|Oral Cancer News|

Nivolumab Could Change Head and Neck Cancer Treatment Paradigm

Source: www.Targetedonc.com
Author: Laura Panjwani
 

“To have an anti–PD-1 agent be proven to improve survival in head and neck cancer in a randomized phase III trial, and the potential for a new FDA approval in the near future is a game changer.” – Robert Ferris, MD, PhD

With the phase III CheckMate-141 trial being stopped early due to the anti–PD-1 agent nivolumab having met its primary endpoint of overall survival improvement in head and neck cancer, Robert Ferris, MD, PhD, couldn’t be more elated.

“This is what I’ve devoted my career to, and it is gratifying to see that really come to pass,” said Ferris, professor and chief, Division of Head and Neck Surgery, vice chair for Clinical Operations, associate director for Translational Research, and coleader of the Cancer Immunology Program at the University of Pittsburgh Cancer Institute, in an exclusive interview with Targeted Oncology.

“To have an anti–PD-1 agent be proven to improve survival in head and neck cancer in a randomized phase III trial, and the potential for a new FDA approval in the near future is a game changer. There is now hope for a lot of patients and physicians who have been frustrated by this difficult-to-treat disease. This opens up a whole new class of therapies for this population.”

Ferris, who acted as cochair/coprimary investigator for the trial alongside Maura Gillison, MD, PhD, Ohio State University, said the trial pitted nivolumab against the investigator’s choice of cetuximab (Erbitux), methotrexate, or docetaxel in patients with platinum-refractory squamous cell carcinoma of the head and neck (SCCHN).

Eligible patients who are still enrolled in the study are now able to continue their current treatment regimen, or switch over to nivolumab. Ferris says the prospect of having a new drug available for SCCHN is exciting, especially considering the last FDA approval for the disease type came in 2006.

“It was 2006 when cetuximab was approved and that was a relatively modest advance, although it was the first targeted therapy. We have a population without any other therapeutic options and a very rapid progression,” he said.

“Anti–PD-1 agents have had promising data in melanoma and squamous non–small cell lung cancer (NSCLC). Squamous NSCLC genomically resembles HPV-negative head and neck cancer in its behavior regarding carcinogen exposure. Therefore, we felt it might respond well to anti–PD-1 agents, too. We designed the study to hopefully create something new and effective for an essentially hopeless palliative group of patients.”

The phase III data have not yet been released from the trial, though early discontinuation has generated significant excitement in the field. The trial was scheduled to run until October 2016, has generated significant excitement in the field, says Ferris, who is a primary author on the abstract submitted for presentation at the ASCO Annual Meeting.

Ferris says the study was designed reflect the idea that there are different standards of care for SCCHN throughout the world, which is why cetuximab, methotrexate, or docetaxel were chosen for the control arms.

“We still don’t have public data for what all of the standard of care selections were, but we do know that cetuximab tends to be used more in North America. Meanwhile, the other 2 agents are more likely to be used in Europe and other countries because cetuximab is not approved there,” he said.

“The benefits are really very modest with those single-agent treatments and they are toxic. There is very much a need for a new treatment. We are very interested in the toxicity profile of nivolumab, as it has proven to be well tolerated in other cancers.”

Ferris adds that the excitement generated in the field stems from the revelation of efficacy for pembrolizumab (Keytruda) at the 2015 ASCO Annual Meeting, saying the data from both pembrolizumab and nivolumab “appear to be very similar.”

“There was a suspicion that nivolumab would be promising in head and neck cancer, as well. There is a great deal of buzz from medical oncology leaders all over the country regarding this. People have really been waiting with bated breath for something for our patients. This is a real win for the community and for a population of patients with a devastating disease in a very important area of the body,” he said.

“This disease can disrupt speaking, drinking, swallowing, and has catastrophic consequences. I expect enthusiasm and support from the community regarding this.”

*This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.

February, 2016|Oral Cancer News|

Keytruda doubles efficacy of only targeted therapy for head and neck cancer

Source: www.curetoday.com
Author: Lauren M. Green

The immunotherapy Keytruda (pembrolizumab), in a recent study, proved twice as effective for the treatment of head and neck cancer as Erbitux (cetuximab), the only targeted therapy indicated as a therapy for the disease.

The multisite study offers the largest experience to date of how immunotherapy can be deployed in patients with head and neck cancer, and could change the way the disease is treated. The findings were announced May 29 during the annual meeting of the American Society of Clinical Oncology, a gathering of nearly 30,000 oncology professionals taking place in Chicago.

Keytruda is an antibody designed to disable the protein PD-1 so it cannot do its job of keeping the immune system in check; this allows T cells to become more active in recognizing and fighting cancer cells. In the study, investigators found that the drug produced broad and durable responses in patients with advanced head and neck cancer.

Fifty-six percent of patients in the study experienced some tumor shrinkage with Keytruda, and 86 percent of those patients continued to respond to treatment at data cutoff on March 23, 2015. Keytruda produced an overall response rate (ORR) of 25 percent, and it proved active in both HPV (human papillomavirus)-positive and HPV-negative patients.

“The efficacy was remarkable — pembrolizumab seems to be roughly twice as effective, when measured by response, as our only targeted therapy, cetuximab,” said Tanguy Seiwart, an assistant professor of medicine and associate leader of the head and neck cancer program at the University of Chicago, who presented the results in a press briefing during the ASCO meeting. “We have high hopes that immunotherapy will change the way we treat head and neck cancer.”

Recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) has a poor prognosis with a median overall survival (OS) of 13 months in patients treated in the first-line setting, and six months in previously treated patients. Previously treated patients made up the majority of the population of the study, which built on earlier findings from the KEYNOTE-012 study (NCT01848834). In that study, Keytruda — administered at 10 mg/kg every two weeks — had a 20 percent response rate in patients with advanced HNSCC whose tumors were positive for the protein PD-L1.

The findings reported May 29 were based on results from an expansion of that first trial, which involved 132 patients with advanced HNSCC who were recruited regardless of their PD-L1 or HPV status. Importantly, said Seiwert, patients in this cohort received a fixed dose of Keytruda (200 mg every three weeks), representing “a very convenient dosing schedule.”

Eligible patients had measureable disease based on RECIST 1.1 response evaluation criteria and an ECOG performance status of 0 or 1. The majority of enrollees were male (83 percent), and 56.8 percent had received two or more lines of therapy for disease recurrence. Radiographic imaging was used to assess tumor response every eight weeks. Patients were treated as long as they didn’t show progression of disease or as long as they demonstrated clinical improvement, Seiwert explained.

Of 117 evaluable patients, 29 (24.8 percent; [95 percent confidence interval (CI), 17.3–33.6]) responded to treatment with Keytruda. For patients with HPV-positive HNSCC, the ORR was 20.6 percent, and in the HPV-negative cohort, ORR was 27.2 percent.

“In addition to the 25 percent response rate,” said Seiwert, “about 25 percent also had stable disease, so when we take these together, we have a disease control rate of about 50 percent, which is remarkable in this disease, especially in a heavily pretreated population.”

Moreover, he said, about two-thirds of patients had received two or more prior lines of therapy, which generally is an indicator of a very poor prognosis.

For the 56 percent of patients whose tumors decreased in size, Seiwert said the responses often occurred early at eight or 16 weeks, although there were a few outliers with late responses.

“Importantly, those patients who did respond oftentimes continued to have responses — 86 percent of patients had durable responses in this cohort,” he continued, adding that not only are responders remaining on the therapy, but so are many patients who have stable disease, with a total of 40 patients staying on the drug.

“Overall, and in keeping with what we already know about pembrolizumab, this was a very well-tolerated agent,” said Seiwert, “certainly better tolerated than what we usually see in head and neck cancer with aggressive chemotherapy and radiotherapy.”

Serious side effects were reported in fewer than 10 percent of patients. The most common side effects were fatigue (15.2 percent of patients), hypothyroidism (9.1 percent), and decreased appetite and rash, each occurring in 7.6 percent of patients. Four patients discontinued treatment due to immune-related side effects: two due to grade 2 interstitial lung disease and grade 3 colitis, respectively, and two patients for grade 3 pneumonitis.

Analysis of the findings based on biomarker status is ongoing, and Seiwert is hopeful that with the emergence of new potential biomarkers, researchers will be able to pinpoint which patients with HNSCC are most likely to benefit from the immunotherapy.

For example, another related study that Seiwert and colleagues are reporting at ASCO (abstract 6017) has shown that the expression of the gene signature interferon-gamma in head and neck tumors had a very strong negative predictive value of response to Keytruda. “In the future, these results may help us, if validated, to determine which patients should or should not [be given] pembrolizumab,” Seiwert said.

Pembrolizumab versus standard treatment for HNSCC also is being evaluated in two phase 3 trials that are currently recruiting participants (NCT02252042 and NCT02358031).

Source:
Seiwert TY, Haddad RI, Gupta S, et al. Antitumor activity of the anti-PD-1 antibody pembrolizumab in biomarker-unselected patients with R/M head and neck cancer: preliminary results from the KEYNOTE-012 expansion cohort. J Clin Oncol. 2015;(suppl; abstr LBA6008) – See more at: http://www.curetoday.com/articles/keytruda-doubles-efficacy-of-only-targeted-therapy-for-head-and-neck-cancer/2#sthash.44VvpPH4.dpuf

Merck immunotherapy appears effective in head and neck cancer – study | Reuters

Source: www.firstpress.com
Author: Bill Berkrot

 

A Merck & Co drug that helps the immune system fight cancer was about twice as effective as the current standard therapy for patients with recurrent or advanced head and neck cancers, according to study data released on Friday.

A quarter of the 132 patients who received the drug, Keytruda (pembrolizumab), saw their tumors shrink by at least 30 percent. Fifty-six percent of patients experienced at least some tumor shrinkage in the ongoing single drug Phase I study dubbed Keynote-012, researchers reported.

“This is remarkable because we don’t usually see this level of activity with new agents. We have a track record of failure,” said Dr. Tanguy Seiwert, lead investigator of the study from the University of Chicago.

Advanced head and neck cancer is currently treated with Eli Lilly’s Erbitux, known chemically as cetuximab, which typically has a response rate of 10 percent to 13 percent.

“The only thing that works is cetuximab and this looks at least twice as good,” said Seiwert, who was presenting the Keytruda data at the American Society of Clinical Oncology meeting in Chicago.

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Merck shares rose more than 1 percent to $60.43 on the New York Stock Exchange.

Keytruda and Opdivo from Bristol-Myers Squibb Co are at the forefront of a promising new class of drugs called PD-1 inhibitors that block a mechanism tumors use to evade the immune system. Keytruda is approved to treat advanced melanoma and awaits a decision for use in lung cancer. It is being tested against 30 types of cancer alone and in various combinations.

While overall survival data was not yet available, Keytruda and Opdivo have extended survival for some patients in other cancers.

“Response rate doesn’t do this justice,” Seiwert said. “A fraction of those patients will probably have long term survival. It can really make a difference for some patients who have incurable metastatic disease.”

The drug appeared to work as well for patients whose cancer tested positive for human papillomavirus as those who were HPV negative. Some older treatments may be less effective in HPV positive patients, researchers said.

Keytruda was well tolerated with few side effects, Seiwert said. Serious immune-related side effects, such as inflammation of the lungs or colon, were reported in a very small number of patients in the study.

Head and neck cancer is the sixth most common cancer worldwide. Patients with recurrent or metastatic head and neck cancer are usually expected to live about 10 to 12 months.

Reporting by Bill Berkrot in New York; Editing by Diane Craft.

*This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.

Experimental EGFR inhibitor added nothing but rash

Source: www.oncologypractice.com
Author: Neil Osterweil, Oncology Report Digital Network

The addition of the experimental targeted agent zalutumumab to primary curative chemoradiation for head and neck cancers did not improve locoregional control, disease-specific survival, or overall survival at 3 years of follow-up.

The only thing that zalutumumab added to therapy was a skin rash in the large majority of patients who received it, reported Dr. Jens Overgaard, of the department of experimental clinical oncology at Aarhus University, Denmark.

Response to zalutumumab, a monoclonal antibody targeted to the epidermal growth factor receptor (EGFR), was not related to tumor human papillomavirus 16 (HPV/p16) status or to chemoradiotherapy, Dr. Overgaard reported at the Multidisciplinary Head and Neck Cancer Symposium.

The results of the DAHANCA 19 trial echo those of the RTOG (Radiation Oncology Therapy Group) trial 0522, which found no benefit from the addition of the EGFR inhibitor cetuximab (Erbitux) to accelerated cisplatin-based chemoradiotherapy, said Dr. Paul Harari, an invited discussant from the University of Wisconsin, Madison.

“Where I think we have a lot of unanswered questions is acknowledging how little we actually understand about EGFR biology, despite now 40 years of progressive knowledge,” Dr. Harari said.

“We’re now seeing very clearly in molecular and clinical correlate studies that the more we suppress the EGFR, the more we see collateral overexpression of additional RTKs [receptor tyrosine kinases], including members of the HER family, such as HER-3, that enable an escape mechanism for tumors that become resistant to EGFR inhibition,” he said.

Dr. Overgaard and his colleagues in the Danish Head and Neck Cancer Group conducted an open-label, phase III trial in which 619 patients with nonmetastatic squamous cell carcinomas of the larynx, oropharynx, hypopharynx, or oral cavity were randomly assigned to received 66-68 Gy of accelerated radiotherapy with or without zalutumumab 8 mg/kg weekly, with the first dose given a week before the start of radiation. The radiation was given concomitantly with the radiosensitizer nimorazole and, in patients with involved lymph nodes, cisplatin.

A total of 301 patients who received zalutumumab and 307 controls were included in the final intention-to-treat analysis.

At 3-year follow-up, there were no significant differences in either the primary endpoint of locoregional control (76% in zalutumumab-treated patients and 77% of controls) or in the secondary endpoints of disease-specific survival (82% and 85%, respectively) or overall survival (72% and 79%), Dr. Overgaard reported at the symposium, cosponsored by the American Society for Radiation Oncology and the American Society of Clinical Oncology.

Overall, patients who were positive for the HPV/p16 biomarker fared better than p16-negative patients, with an odds ratio for the probability of local control in negative patients of 0.52 (95% confidence interval, 0.36-0.73; P value not reported).

However, regardless of HPV 16 status, the addition of zalutumumab made no difference in the primary endpoint.

In a proportional hazard analysis, factors significantly associated with worse outcomes included worse World Health Organization performance status, higher disease stage, nodal involvement, and HPV/p16 negative status.

Although zalutumumab was generally well tolerated, 94% of patients who received it developed a rash, and of this group, 29% had grade 3 or 4 rash. In all, 11% of patients assigned to zalutumumab had to stop the drug because of rash.

Note:
The trial was sponsored by the Danish Head and Neck Cancer Group. Dr. Overgaard reported having no financial disclosures. Dr. Harari has received research funding from Amgen.

March, 2014|Oral Cancer News|

Erbitux add-on falls short in esophageal cancer

Source: www.medpagetoday.com
Author: Charles Bankhead, Staff Writer, MedPage Today

The addition of a targeted agent to definitive chemoradiation failed to improve survival in an unselected population with esophageal cancer, a randomized trial showed. In fact, patients who received cetuximab (Erbitux) with chemoradiation had significantly worse overall survival (OS) reflected in a 50% increase in the hazard versus chemoradiation alone, reported Thomas Crosby, MD, of Velindre Hospital in Cardiff, Wales, and colleagues.

Investigators could not find any subgroup of patients who benefited from cetuximab, they said in a presentation at the Gastrointestinal Cancers Symposium.

“The addition of cetuximab cannot be recommended to standard definitive chemoradiotherapy in the treatment of unselected patients with esophageal cancer,” Crosby said.

“The use of high-quality definitive chemoradiotherapy in the treatment of localized, poor-prognosis esophageal cancer was associated with excellent survival compared with previous radiotherapy and surgical series,” he added.

Randomized trials have shown that definitive (or primary) chemoradiation improves survival in localized esophageal cancer compared with a single treatment modality. In England, definitive chemoradiation has been used primarily for patients with localized disease that is unsuitable for surgery, Crosby said.

Add-on therapy with cetuximab has improved outcomes in other cancers, notably head and neck cancer and colorectal cancer. The findings provided a rationale for evaluating the addition of cetuximab to primary radiation therapy for localized esophageal cancer.

Crosby presented results of a randomized trial wherein patients with localized (stage I-III) esophageal cancer (less than 10 cm). Patients were excluded if they had celiac lymph-node involvement.

The patients received cisplatin-capecitabine (Xeloda) chemotherapy with or without cetuximab. After 6 weeks of chemotherapy, patients underwent definitive conformal radiation therapy at a total dose of 50 Gy in 25 fractions.

The trial had two stages. The first stage had a primary endpoint of treatment failure-free survival (TFFS), defined as alive at 6 months with no residual cancer in biopsy specimens and no evidence of disease progression outside the radiation therapy field. Secondary endpoints were toxicity, quality of life, overall survival (OS), and feasibility of recruitment. The first stage of the trial had an accrual target of 180 patients.

The trial’s second stage had a primary endpoint of OS and accrual to 420 patients.

However, the trial never reached second stage, but ended after a planned stage one analysis convinced the independent review committee that continued accrual to meet the primary endpoint would be futile.

Treatment and follow-up continued with enrolled patients, and the final analysis included 258 patients who had completed the 6-month assessment of disease status.

Crosby reported that patients randomized to conventional chemoradiation without cetuximab had a TFFS of 77% whereas the cetuximab group had a TFFS of 66%. All survival outcomes favored omission of cetuximab:

Median OS: 25.4 months versus 22.1 months
2-year survival: 56% versus 43.1%
Median progression-free survival: 19.4 months versus 15.9 months
The analysis showed a marked difference in median OS between patients who met the TFFS goal at 6 months and those who did not: 26.7 months versus 8.3 months.

Comparison of OS in the two arms yielded hazard ratio of 1.53 for the cetuximab arm versus chemoradiation only (P=0.035).

In addition to the inferior outcomes with cetuximab, addition of the targeted agent added to the toxicity burden. The cetuximab arm had an 81.4% incidence of grade 3 to 5 toxicity compared with 72.9% without cetuximab.

Patients who received cetuximab in addition to chemoradiation had significantly more grade 3 to 5 dermatologic toxicity (21.7% versus 3.9%, P<0.001) and metabolic/biochemical toxicity (24.0% versus 10.9%, P=0.005).

Additionally, the analysis revealed a trend toward more cardiac adverse events in the cetuximab arm (6.2% versus 1.6%, P=0.053).

The addition of cetuximab also adversely affected adherence to the treatment protocol. Patients in the cetuximab arm were significantly less likely to receive full doses of cisplatin (76.7% versus 89.9%, P=0.005), capecitabine (69.0% versus 85.3%, P=0.002), and radiation therapy (75.2% versus 86.0%, P=0.027).

Additionally, almost a third of patients did not receive the prescribed dose of cetuximab.

“Future strategies to improve the outcome of definitive chemoradiotherapy in esophageal cancer must focus on developing evidence-based biomarkers to select treatments and incorporating newer radiotherapy technologies and targeted systemic treatment to safely intensify treatment, including a higher radiotherapy dose,” Crosby said.

January, 2013|Oral Cancer News|

Scientists find new way to boost cancer drugs

Source: www.drbicuspid.com
Author: DrBicuspid Staff

Shutting down a specific pathway in cancer cells appears to improve the ability of common drugs to wipe those cells out, according to new research from scientists at Fox Chase Cancer Center (Cancer Discovery, January 2013, Vol. 3:1, pp. 96-111).

The new approach appears to enhance the tumor-killing ability of a commonly prescribed class of drugs that includes cetuximab (Erbitux), used to treat head and neck cancers. These drugs work by blocking the activity of the epidermal growth factor receptor (EGFR), which sits on the cell surface and senses cues from the environment, telling cancer cells to grow and divide, according to co-author Igor Astsaturov, MD, PhD, an attending physician in the department of medical oncology at Fox Chase.

In 2010, Dr. Astsaturov and his colleagues identified a pathway in the cell that, when blocked, completely suppressed EGFR activity. Interestingly, the pathway consists of a series of enzymes that, when working in concert, synthesize new molecules of cholesterol.

Working with cancer cells in the lab, the researchers inactivated a key gene in the cholesterol synthesis pathway, and found the cells became more vulnerable to treatment with cetuximab. The same was true in mice that lacked this particular pathway, according to Dr. Astsaturov.

“Most tumors are only moderately sensitive to inhibitors of EGFR, but when these tumors lack an essential gene in the cholesterol pathway, they become exquisitely sensitive to the anti-EGFR drugs,” he said. “The cancers literally melt away in mice.”

The researchers then removed one of the cholesterol genes from the mouse genome and saw that mice developed patchy, scaly skin. When they biopsied this affected skin, they saw no activity of the EGFR protein, reaffirming that shutting down cholesterol synthesis interrupts EGFR.

When the cholesterol biosynthesis pathway is blocked, the normal chain of events that creates a cholesterol molecule is interrupted, and cells accumulate intermediate products of cholesterol that block the normal movement of substances around the cell, according to the researchers. This cellular traffic jam makes it difficult for the cell to transport important components, such as EGFR, which has to move between the inside of the cell and its surface to function properly.

Eventually, researchers can design drugs or look for existing ones that block this cholesterol synthesis pathway, Dr. Astsaturov noted. For now, his lab is trying to uncover more details of how the pathway works, the role of each protein that is involved, and whether if, by blocking a protein, they can wipe out tumors in humans that evade current therapies.

January, 2013|Oral Cancer News|

Germany’s Merck halts supply of cancer drug to Greek hospitals

Source: Reuters.com

Date: November 3, 2012

German pharmaceuticals firm Merck KGaA is no longer delivering cancer drug Erbitux to Greek hospitals, a spokesman said on Saturday, the latest sign of how an economic and budget crisis is hurting frontline public services.

Drugmakers raised concerns with EU leaders earlier this year over supplies to the euro zone’s crisis-hit southern half and Germany’s Biotest in June was the first to stop shipments to Greece because of unpaid bills.

Publicly-owned hospitals in some countries worst hit by the euro zone debt crisis had been struggling to pay their bills, Merck’s chief financial officer, Matthias Zachert, was quoted as saying by German paper Boersen-Zeitung in an interview on Saturday.

He said however that the only country where Merck had stopped deliveries was Greece.

“It only affects Greece, where we have been faced with many problems. It’s just the one product,” he told the paper.

A spokesman for the company told Reuters that the drug concerned was Erbitux and that ordinary Greeks can still purchase it from pharmacies.

Some countries have taken action to pay bills, such as in Spain, where the government has said it will help hospitals to pay off debts.

“That has improved things, even though the situation should still be regarded as critical for the coming years,” Zachert said.

Erbitux is Merck’s second best-selling prescription drug, bringing in sales of 855 million euros ($1.1 billion) in 2011 from treating bowel cancer and head and neck cancer. ($1 = 0.7785 euros)

This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.

November, 2012|Oral Cancer News|

Facing the facts: HPV-associated head and neck cancers get a second look

Source: www.curetoday.com
Author: Charlotte Huff

Kevin Pruyne knew he didn’t fit the stereotype of a hard drinker or heavy smoker who one day develops an oral cancer.

The 52-year-old mechanic had been working a three-week stint in a remote section of northern Alaska, repairing trucks on an oil field, when he noticed a hard lump beneath his jaw while shaving. For nearly three months, as Pruyne was prescribed antibiotics for a possible infection and then later shuttled between physician specialists, he kept hearing the same thing: the lump could not be cancer.

Pruyne only occasionally consumed alcohol and had never smoked. His wife, Kathy, began researching her husband’s symptoms, which included repetitive throat clearing, a nagging sensation that something was lodged in his throat and ringing in his ears. And the lump, which looked like the top half of an egg, felt solid to the touch.

This wasn’t some inflamed lymph node from a lingering head cold, Kathy Pruyne says. “He had every symptom [of cancer], but nobody would listen to me.”

Pruyne received a diagnosis of stage 4 oral cancer, which started with a tumor at the base of his tongue. He had already begun chemotherapy when he learned that researchers had discovered an association between the human papillomavirus (HPV) and increasing rates of oropharyngeal cancers. He asked that his tissue be tested; the results came back positive. Pruyne says he wanted to know whether his cancer was caused by HPV because “the prognosis is considerably better with HPV-positive cancer.” He adds he “wanted to hear that there was a better chance of a cure.”

An Explosion of Cases

For researchers and clinicians alike, determining appropriate treatment has taken on new urgency: HPV-positive oropharyngeal malignancies—most typically found on the tonsils or at the base of the tongue—increased 225 percent from 1988 to 2004. If current trends continue, HPV-positive oral cancer cases could soon surpass cervical cancer diagnoses, according to a 2011 study published in the Journal of Clinical Oncology.

As researchers have revisited data from prior oral cancer treatment studies, they’re realizing that patients with HPV-positive tumors respond better to chemotherapy and radiation. One study, which retrospectively analyzed treatment outcomes for stage 3 and stage 4 oropharyngeal patients based on their HPV status, found that the three-year overall survival rate was 82.4 percent in patients with HPV-positive tumors. Among those who tested negative, the three-year overall survival rate was 57.1 percent, according to the findings published in 2010 in The New England Journal of Medicine.

With that in mind, research trials are being launched to determine whether treatment can be modified in some way or even dialed back. The goal? To achieve the same survival with fewer of the swallowing difficulties, taste problems and other debilitating side effects.

“For a subset of patients, we’ve actually achieved a pretty high cure rate,” says James Rocco, MD, PhD, a head and neck surgeon at Massachusetts Eye and Ear Infirmary, and director of head and neck cancer research at Massachusetts General Hospital. “And the question is: Can we maintain that cure and reduce some of the major side effects of treatment?”

But researchers and oncologists have only just begun to understand HPV-positive malignancies. “It’s very clear that HPV-positive oropharyngeal cancer is a completely different entity from HPV-negative,” says Stephen Liu, MD, a head and neck cancer specialist, and an assistant professor of medicine at the University of Southern California.

“We think that it’s going to impact treatment in the future,” Liu adds. But, he stresses, outside of a clinical trial, he “would really discourage anyone from receiving less treatment because their tumor is HPV-positive.”

Identifying the Virus

Traditionally, tobacco and alcohol use have been the primary culprits for triggering cancers in the oropharynx and nearby areas of the mouth, as well as other structures in the throat, such as the larynx. Each year, nearly 40,000 Americans develop cancer of the oral cavity or pharynx. Men are more than twice as likely to receive a diagnosis.

But, until recent years, not someone like David Hastings. The certified public accountant was 58 years old, a lean cyclist who rode some 100 miles each week, when he learned six years ago that he had stage 4 oropharyngeal cancer located at the base of his tongue. Clinicians at H. Lee Moffitt Cancer Center and Research Institute in Tampa, Fla., also were puzzled, as the Gulfport resident tells it. “They said the typical oral cancer patient is a man in his 60s or 70s who sits in a bar all day and drinks and smokes.”

The association with HPV emerged from a perplexing conundrum, says Kian Ang, MD, PhD, a professor in the department of radiation oncology at M.D. Anderson Cancer Center in Houston. As cigarette smoking has declined in recent decades, so have head and neck cancers, with the exception of tumors in the oropharynx. (The region encompasses the middle section of the throat, along with the back portion of the tongue, the soft palate and the tonsils.) That statistical anomaly, Ang says, “gave us the first clue that something else might be going on.”

 

Starting with a pivotal study published in 2000, researchers began honing in on the role of HPV. Of the 150-plus strains in the HPV family, more than 40 are believed to be transmitted through sexual contact, including anal, genital and oral, according to the National Cancer Institute. The body’s immune system typically eradicates the viruses in a few years before any symptoms emerge (but, in some cases, the cells remain molecularly altered forever). Several of the HPV strains to date, most frequently HPV type 16, have been linked to oral malignancies.

Increasingly, HPV-16 has become a major player in those oral malignancies, according to last year’s Journal of Clinical Oncology study, which projected an explosion in cases in the decades to come.

When researchers studied 271 tissue samples in previously diagnosed patients, HPV prevalence was identified in only 16.3 percent of those collected between 1984 and 1989. Between 2000 and 2004, 72.7 percent of specimens tested positive, a trend that also perhaps correlates with population-wide increases in oral sex, the researchers wrote.

The analysis also highlighted survival differences. If tumors tested HPV-positive, the median survival was nearly 11 years versus 1.6 years for people whose tumors didn’t carry the virus.

Some of the strides in oral cancer treatment that physicians thought they were achieving can at least be partially explained by the emergence of a less aggressive form of cancer, Ang says. “The other part of the improvement,” he says, “is really due to the addition of chemotherapy and the use of high-precision radiation.”

Multifaceted Treatment

Cancers located in the tonsils or at the base of the tongue can sometimes spread undetected, not becoming visible until they’ve reached the nearby lymph nodes. Some early symptoms include swallowing difficulties or a sudden change or hoarseness in the voice. Like Pruyne, Hastings first became concerned when he felt a mysterious lump while shaving. “Totally painless, no sore throat—nothing,” he says.

Oropharyngeal tumors can be classified as stage 3 or 4 but still be considered localized, as long as they have not spread beyond lymph nodes and structures in the head and neck. Pruyne, whose cancer had migrated to numerous nodes on his neck’s right side, recalls how his oncologist hurried out of the room when his imaging test results became available.

The doctor had already warned Pruyne that he could offer relatively little help if the cancer had spread to his chest. “When he came back up, he was visibly relieved,” Pruyne recalls. “And he said, ‘Your lungs are clear.’”

To thwart oropharyngeal malignancies, cancer specialists may incorporate a mix of treatments, including surgery, radiation and chemotherapy, depending upon the location and the aggressiveness of the tumor involved. Ang estimates that only about one-third of patients will undergo surgery. If the tumor can be removed and there’s no evidence that it’s spread to lymph nodes, radiation may not be needed, he says.

 

But if there’s any concern, patients may receive six weeks of radiation for smaller tumors and seven weeks for larger ones, Ang says. Intensity-modulated radiation therapy (IMRT) is used because it better targets the radiation and thus can limit damage to the salivary glands, reducing dry mouth, as well as damage to other normal tissues, Ang says.

For larger and more aggressive tumors, adding chemotherapy to radiation therapy has been shown to extend survival. One meta-analysis published last year, based on 87 studies involving more than 16,000 patients, analyzed results by tumor location. Researchers found that the combination approach increased five-year overall survival by 8.1 percent in oropharyngeal patients compared with those who didn’t receive any chemotherapy.

The chemotherapy is believed to boost the effectiveness of the radiation, but at a cost—amplified side effects for the patient. The list of potential side effects is lengthy, with so many vulnerable structures and nerves packed into the head and neck area, Liu says. Patients can develop ulcers in their mouth and down their throat, he says. Their salivary glands can generate thick secretions that make it difficult to swallow and to eat.

“The ability to taste, to speak, to salivate,” says Liu, ticking off several more. “Dry mouth. These things can often be permanent. It’s a necessary evil right now because we do what we need to do to cure the cancer.”

Pruyne received two cycles of a cisplatin-based protocol that also included Taxotere (docetaxel) and 5-FU (fluorouracil). Then he started the biologic agent Erbitux (cetuximab) along with hefty doses of IMRT, delivered twice daily for six weeks.

Pruyne’s oncologist warned him that the treatment would be difficult, and it was. He endured radiation burns around the right side of his neck and had to use a feeding tube for two months.

Dialing Back

Although radiation and chemotherapy can be difficult, some patients prefer to take that route, rather than run the risks of surgery, Rocco says. “For advanced local disease, removing the back of the tongue or the soft palate has huge consequences for people,” Rocco says. “They can’t eat. They don’t speak so well.”

But given that patients with HPV-positive tumors are typically diagnosed at a younger age, with potentially decades ahead of them to cope with long-term side effects, the aggressiveness of today’s chemotherapy and radiation regimens are also questionable, he says.

Clinical trials are recruiting patients to answer a question that’s relatively rare in cancer: Can treatment be ramped down? One closely watched phase 3 trial will assess whether Erbitux works as well in HPV-positive patients as the long-standing cisplatin-based chemotherapy regimen.

Cisplatin has been one of the standard drugs used in head and neck cancer, but it’s “very toxic,” says Andy Trotti III, MD, the study’s principal investigator and director of radiation oncology clinical research at Moffitt Cancer Center. The platinum-based drug can impact kidney function and sometimes damage hearing, among other side effects, he says.

Erbitux, which targets the epidermal growth factor receptor (EGFR), primarily affects the skin, Trotti says. In the phase 3 trial, now recruiting HPV-positive patients, the five-year overall survival of patients on Erbitux will be compared with those taking cisplatin. Both groups will receive IMRT.

Another ongoing trial is looking at whether the IMRT regimen can be shortened from six to five weeks, thereby delivering a lower dose of radiation in HPV-positive patients. The patients enrolled in that phase 2 trial, who also will receive cisplatin,  paclitaxel and Erbitux, will be followed for two years.

The study represents a “first step” toward learning whether less radiation can be safely prescribed for HPV-positive patients, Liu says. Since radiation’s effects are cumulative, the extra week of radiation adds “a significant amount of toxicity.”

A New Era in Treatment

Meanwhile, the impact of HPV status on surgical decisions appears to be the subject of some unresolved debate. Given that HPV-positive oropharyngeal malignancies respond well to chemotherapy and radiation, Trotti says, “there has been a real trend away from surgery.”

But new surgical techniques are providing other options for HPV-positive patients who might prefer to limit the long-term side effects of chemotherapy and radiation, says Bert O’Malley, Jr., MD, chairman of the department of otorhinolaryngology of the University of Pennsylvania Health System.

Along with a physician colleague, O’Malley has developed a robotic surgery protocol called TransOral Robotic Surgery. With the assistance of tiny robotic arms and three-dimensional cameras, O’Malley operates through the patient’s mouth, enabling him to remove difficult-to-reach tumors.

A surgery that previously required between six and 16 hours might only take two, he says. Also the approach results in less scarring and fewer surgical complications than the traditional surgery, which may require the jaw to be split, he says.

It’s a new era in HPV-positive treatment, Rocco says. To make his point, he tells of a patient who recently walked in asking to be referred for robotic surgery. The gold standard is still to wait for clinical trial results, but that could take five-plus years, he adds.

HPV-positive patients are frequently “savvy young professionals in the prime of life,” who sort through the latest research online, Rocco points out.

“There are people who are risk-takers,” he says. “They’ll look at the data, and they’ll make a decision, weighing cure and long-term side effects.”

Despite the rigors of treatment, Pruyne was able to resume his job near the Arctic Circle within a few months. He hopes to soon be telling a tale similar to Hastings’, who returned to his biking routine about a year after wrapping up treatment.

Hastings still copes with dry mouth and a reduced ability to taste. But the last time he visited Moffitt for an annual checkup, it felt more like a social call. After some chatting, he quips: “They said, ‘Get out of here. We need to spend more time with people who are sick.’”

 

Third Head and Neck Indication for Erbitux

Source: The ASCO Post, January 1, 2012, Volume 3, Issue 1, Matthew Stenger

 

In the Clinic provides overviews of novel oncology agents, addressing indications, mechanisms, administration recommendations, safety profiles, and other essential information needed for the appropriate clinical use of these drugs.Cetuximab (Erbitux) was recently approved by the FDA for use in combination with platinum-based therapy plus fluorouracil (5-FU) for the first-line treatment of patients with recurrent locoregional disease or metastatic squamous cell carcinoma of the head and neck.1-3 Cetuximab has prior indications in combination with radiation therapy in locally or regionally advanced squamous cell head and neck cancer and in recurrent or metastatic head and neck cancer that has progressed after platinum-based therapy. It also has indications in colorectal cancer.

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The most recent approval is based primarily on results of a study conducted outside the United States in 442 patients with metastatic or locally recurrent squamous cell carcinoma of the head and neck who were not suitable for curative treatment with surgery or radiation. The study used a European Union (EU)-approved cetuximab rather than the U.S.-approved cetuximab (Erbitux). Erbitux provides approximately 22% higher exposure than the EU-approved cetuximab; these pharmacokinetic data, together with the results of the study conducted in Europe and other data using Erbitux establish the safety and efficacy of Erbitux at the recommended dose.In this trial, the addition of cetuximab (n = 222) to platinum-based therapy plus 5-FU (n = 220) significantly increased median overall survival from 7.4 to 10.1 months, representing a 20% reduction in risk of death (HR = 0.80, P = .034), and significantly increased median progression-free survival from 3.3 to 5.5 months, representing a 43% reduction in risk of disease progression (HR = 0.57, P < .0001). Objective response rates were 35.6% in the cetuximab group and 19.5% in the chemotherapy-alone group (P = .0001).


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How It Works

Cetuximab is an IgG1 monoclonal antibody that inhibits ligand-binding to the epidermal growth factor receptor (EGFR) on both normal and tumor cells. Binding of cetuximab to EGFR blocks phosphorylation and activation of receptor-associated kinases, resulting in inhibition of cell growth, induction of apoptosis, and decreased production of matrix metalloproteinase and vascular endothelial growth factor. In cells with activating KRAS mutation, however, the KRAS proteins are continuously active and are independent of EGFR regulation. Cetuximab also stimulates antibody-dependent cell-mediated cytotoxicity and enhances the activity of a number of chemotherapeutic agents, including cisplatin.

How It Is Given

For the new indication, the recommended dose is 400 mg/m2 as a 120-minute IV infusion, with a maximum rate of 10 mg/min, on the day that platinum-based therapy plus 5-FU is started. The infusion must be completed 1 hour prior to beginning platinum-based therapy plus 5-FU. The subsequent weekly dose is 250 mg/m2 over 60 minutes until disease progression or unacceptable toxicity.Patients should be premedicated with an H1 antagonist (eg, diphenhydramine, 50 mg) IV 30 to 60 minutes before the first dose of cetuximab; premedication for subsequent doses depends on clinical judgment and presence/severity of prior infusion reactions. The infusion rate should be reduced by 50% for grade 1 or 2 or nonserious grade 3 infusion reactions. Cetuximab should be immediately and permanently discontinued for severe infusion reactions.In cases of severe acneiform rash, administration should be delayed by 1 to 2 weeks, and cetuximab discontinued at the fourth occurrence. The weekly dose should be reduced to 200 mg/m2 after the second occurrence and 150 mg/m2 after the third.Cetuximab should be administered via infusion pump or syringe pump and through a low protein-binding 0.22-micrometer in-line filter.

Safety Profile

Cetuximab carries a boxed warning for infusion reactions and cardiopulmonary arrest. Serious infusion reactions occurred in approximately 3% of patients in clinical trials, with fatal outcome in less than 1 in 1,000 cases. In patients with squamous cell carcinoma of the head and neck receiving cetuximab, cardiopulmonary arrest or sudden death occurred in 2% of those receiving radiotherapy and in 3% of those receving platinum-based therapy plus 5-FU. Serum electrolytes, including magnesium, potassium, and calcium, must be carefully monitored during and after cetuximab administration.In the trial supporting the current indication, the most common adverse reactions (≥ 25%) in patients in the cetuximab group were nausea, anemia, vomiting, neutropenia, rash, asthenia, diarrhea, and anorexia; conjunctivitis occurred in 10%. Other adverse reactions, sometimes severe, caused by cetuximab included infusion reactions, hypomagnesemia, hypocalcemia, and hypokalemia. Death attributed to cardiovascular event or sudden death was reported in 3.2% of the patients in the cetuximab group and in 1.9% in the chemotherapy alone group.

 This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.

January, 2012|Oral Cancer News|