It looks as if all vaccine trials are headed this way. Using a vaccine as a control makes the vaccine your are testing seem less dangerous. Here is another example.
Data presented today at the 25th European Society of Paediatric Infectious Diseases (ESPID) in Porto, Portugal, show that the GSK cervical cancer candidate vaccine induced high immune response levels against the cancer-causing human papillomavirus (HPV) 16 and 18 types, while remaining well-tolerated, in adolescent girls over a period of 18 months after vaccination1. As part of this trial, 2,067 adolescent girls were vaccinated, making this the largest clinical trial in cervical cancer vaccination in adolescent girls conducted to date1,2,3.
The immune response levels against cancer-causing HPV types 16 and 18 in 10 to 14 year old girls were significantly higher when compared to 15 to 25 year old women in other trials, and remained high over 18 months1. The high immune response induced in adolescent girls is likely to result in long-term, continued protection after vaccination against HPV types 16 and 18, and may provide additional protection against other cancer-causing HPV types1. Long-term protection is particularly important when vaccinating adolescent girls as they will need to benefit from protection for longer. HPV 16 and 18 are the most prevalent cancer-causing HPV types worldwide, responsible for 70 percent of all cervical cancer cases5.
These new data also show that the GSK cervical cancer candidate vaccine was well-tolerated in adolescent girls 18 months after vaccination1. The number of withdrawals as a result of adverse events and the number of adolescent girls experiencing at least one serious adverse event over that time were similar to those reported in the control group, who were vaccinated with Havrix®, a GSK hepatitis A vaccination.
Tino Schwarz, Head of the Central Laboratory at the Stiftung Juliusspital, Academic Teaching Hospital of the University of Wuerzburg in Germany and a lead investigator of the study, said: "The long-term protection and tolerability of this vaccine have already been demonstrated in 15-25 year old women. Now these great results confirm that these benefits can also be seen in adolescent girls on a large scale."
Clinical trials in 15 to 25 year old women have already demonstrated that the GSK cervical cancer candidate vaccine provides 100 percent sustained protection against precancerous lesions caused by HPV types 16 and 18 over 5.5 years4. Data also show preliminary evidence that the vaccine provides additional protection against precancerous lesions due to cancer-causing HPV, regardless of virus type over 5.5 years4. Given the high immune response in adolescents, maintained over 18 months, it is likely that these long-term benefits could also be expected in adolescent girls1.
The GSK cervical cancer candidate vaccine is formulated with a new proprietary adjuvant system, AS04, which has been shown to enhance the immune response of the candidate vaccine when compared to the same vaccine formulated with GSK's conventional aluminium hydroxide adjuvant6. In clinical trials, the AS04 adjuvanted GSK cervical cancer candidate vaccine has been shown to be well tolerated4,6.
"GSK has undertaken an extensive clinical development programme to document the efficacy and safety of this vaccine, which has the potential to substantially reduce the worldwide disease burden related to cervical cancer and pre-cancer " Hugues Bogaerts, MD ,Vice President of Worldwide Medical Affairs HPV at GSK Biologicals commented.
Results from the single largest phase III efficacy trial conducted to date of the GSK cervical cancer candidate vaccine are expected in the coming months. GSK has also initiated a head-to-head clinical study in women aged 18 to 45, to compare the immune response and safety profile of its cervical cancer candidate vaccine with Merck's cervical cancer vaccine.
GSK submitted a biological licence application (BLA) for the GSK cervical cancer candidate vaccine to the U.S. Food and Drug Administration (FDA) in March 2007. Earlier regulatory filings have been submitted to the European Medicines Agency (EMEA) and there have been regulatory filings in Africa, Asia, Australia and Latin America.
About the study
These data are the results from an 18-month extension study, which evaluated the persistence of vaccine-induced immune response and safety compared with a control group receiving a hepatitis A virus vaccine formulated with conventional aluminium hydroxide adjuvant. Girls aged 10-14 years enrolled from Asia Pacific, Europe and Latin America were vaccinated and evaluated. This study initially showed that vaccination with the GSK cervical cancer candidate vaccine was immunogenic and well-tolerated in girls aged 10-14 up to 7 months after the first dose7.
About cervical cancer and its progression
Approximately 100 types of human papillomavirus have been identified to date and of these, only 15 virus types are considered to cause cervical cancer3. Throughout their lifetime women are exposed to a number of these types, therefore every woman is at risk of developing cervical cancer as a result of persistent infection with cancer-causing virus types5,8.
Cervical cancer develops as a result of a persistent infection of cancer-causing human papillomavirus5. Persistent infection with a cancer-causing virus type leads to the formation of abnormal cells in the cervix, which over time become cancerous. The progression to cervical cancer is largely asymptomatic and takes place over many years in most cases. Cervical cancer is the second most common cancer among women under 45 years of age after breast cancer.9
About the GlaxoSmithKline cervical cancer candidate vaccine
The GSK cervical cancer candidate vaccine was developed to prevent infection and lesions from the two most prevalent cancer-causing types of human papillomavirus, specifically human papillomavirus 16 and 18. It is formulated with the proprietary adjuvant system, AS04, designed to provide strong and sustained antibody levels over time. More than 22,000 women worldwide have been vaccinated with the GSK cervical cancer candidate vaccine as part of completed and ongoing clinical trials. Phase III studies are under way in more than 25 countries with more than 41,000 subjects enrolled in ongoing trials.
GlaxoSmithKline - one of the world's leading research-based pharmaceutical and healthcare companies - is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For company information, please visit www.gsk.com/media.
GSK Biologicals (GSK Bio), one of the world's leading vaccine manufacturers, is headquartered in Rixensart, Belgium, where the majority of GlaxoSmithKline's activities in the field of vaccine research, development and production are conducted. GSK Bio employs more than 1,500 scientists, who are devoted to discovering new vaccines and developing more cost-effective and convenient combination products to prevent infections that cause serious medical problems worldwide. In 2006, GSK Bio distributed more than 1.1 billion doses of vaccines to 169 countries in both the developed and the developing world - an average of 3 million doses a day. Of those vaccine doses, approximately 136 million were doses of combination paediatric vaccines which protect the world's children with up to six diseases in one vaccine.
1 Rombo L, Dubin G. Long-term safety and immunogenicity of a cervical cancer candidate vaccine in 10-14-year-old adolescent girls. Presented at the European Society of Paediatric Infectious Diseases (ESPID) annual meeting on 2-5 May 2007
2 Block SL, Nolan T, et al. Comparison of the Immunogenicity and Reactogenicity of a Prophylactic Quadrivalent Human Papillomavirus (Types 6, 11, 16, and 18) L1 Virus-Like Particle Vaccine in Male and Female Adolescents and Young Adult Women. Pediatrics 2006; 118, 5
3 Reisinger KS, Block SL, et al. Safety and Persistent Immunogenicity of a Quadrivalent Human Papillomavirus Types 6, 11, 16, 18 L1 Virus-Like Particle Vaccine in Preadolescents and Adolescents The Pediatric Infectious Disease Journal 2007; 26, 3
4. Gall SA, et al. Substantial impact on precancerous lesions and HPV infections through 5.5 years in women vaccinated with the HPV-16/18 L1 VLP AS04 candidate vaccine. Presented at the American Association for Cancer Research (AACR) annual meeting on 14-16 April 2007
5 Muñoz N, Bosch FX, de Sanjose S,et al. Epidemiologic classification of human papillomavirus types associated with cervical cancer. N Engl J Med 2003; 348: 518-527
6 Giannini S, Hanon E, Moris P et al. Enhanced humoral and memory B cellular immunity using HPV16/18 L1 VLP vaccine formulated with the MPL/aluminium salt combination (AS04) compared to aluminium salt only. Vaccine 2006, 24: 5937-5949
7 Rombo L, et al. AS04 Adjuvanted Human Papillomavirus (HPV) 16/18 L1 Virus-Like Particle (VLP) Vaccine for the Prevention of Cervical Cancer is Well-Tolerated and Immunogenic in 10-14-Year-Old Adolescent Girls. Presented at the European Society for Paediatric Infectious Diseases (ESPID) annual meeting on 5 May 2006
8 Baseman JG, Koutsky LA. The epidemiology of human papillomavirus infections J Clin Virol 2005; 32 Suppl 1; S16-24
9 Ferlay J, Bray P, Pisani P, et al. GLOBOCAN 2002: Cancer incidence, mortality and prevalence worldwide. IARC CancerBase No. 5, version 2.0. IARCPress, Lyon, 2004. Available at: http://www-dep.iarc.fr.