Single Dose of HPV-16/18 Vaccine Looks to Be Sufficient

Source: www.medscape.comAuthor: Jenni Laidman A single dose of a vaccine against human papillomavirus (HPV) may prevent cervical cancer as effectively as the standard three-dose regimen, researchers concluded after analyzing the combined results of two large vaccine trials. The HPV vaccine in these studies was Cervarix (GlaxoSmithKline), which is effective against HPV strains 16/18. If randomized controlled trials ultimately support the result of this post hoc analysis, it could broaden protection against cervical cancer in areas of the world where vaccination programs are hardest to administer and where cervical cancer is disproportionately burdensome, the study authors say. "Even if you ignore the expense, the feasibility of implementing and getting back to individuals for a second and third dose is quite challenging, especially in places where there is no infrastructure," coauthor Cosette Wheeler, PhD, Regents Professor, Pathology and Obstetrics and Gynecology, University of New Mexico Health Sciences Center in Albuquerque, told Medscape Medical News. The studies are published online June 10 in the Lancet Oncology. The possibility of a single-dose HPV vaccine is "a huge public health win," coauthor Aimée R. Kreimer, PhD, Investigator, Division of Cancer Epidemiology & Genetics, National Cancer Institute, Bethesda, Maryland, told Medscape Medical News. "Even if one dose protects only against HPV types included in the vaccine formulation, if we vaccinated most girls, we would have the chance to reduce cervical cancer by around 75%." That's the exciting part, Dr Wheeler added. "If we're able to achieve success with one dose, or frankly even with two doses, that makes the possibility [...]

Trial Confirms Efficacy of HPV Vaccine, Shows Cross-Protection

Source: National Cancer Institute End-of-trial results from a trial testing Cervarix, a vaccine against human papillomavirus (HPV) types 16 and 18, showed that the vaccine continued to provide substantial protection against cervical precancers 4 years after vaccination. Cervarix provided almost complete protection in young women who had no evidence of exposure to HPV at the time of vaccination. The vaccine provided less protection for the total vaccinated cohort and was less effective with increasing age at vaccination. These findings reflect the vaccine’s lack of effectiveness against infections acquired before vaccination. The vaccine also partially protected women against four types of HPV that are not targeted by the vaccine. (Although HPV-16 and -18 cause about 70 percent of cervical cancers worldwide, as many as 15 HPV types can cause cancer.) These results from the PATRICIA trial (Papilloma Trial against Cancer in Young Adults) were published online November 9 in Lancet Oncology in two separate papers, available here and here. The PATRICIA trial enrolled 18,644 young women between the ages of 15 and 25 from 14 countries. The participants were randomly assigned to receive either three doses of Cervarix or three doses of a hepatitis A vaccine as a control. Results from the interim analysis, published in July 2009, showed that the vaccine greatly reduced the risk of grade 2 cervical intraepithelial neoplasias and higher (CIN2+). The new analysis shows that, 4 years after vaccination, Cervarix provided complete protection against grade 3 cervical intraepithelial neoplasias or higher (CIN3+) associated with HPV-16 and [...]

2011-11-29T18:55:35-07:00November, 2011|Oral Cancer News|
Go to Top