PHILADELPHIA, Nov. 1 /PRNewswire-FirstCall/ -- GlaxoSmithKline today presented data showing that its investigational human papillomavirus (HPV) 16/18 L1 vaccine formulated with an innovative adjuvant, AS04, induced a stronger immune response, when compared to the same vaccine formulated with aluminum salt alone. This stronger response was sustained over 3.5 years post vaccination in women. These results, based on three separate assessments, including in-vitro evaluation of biological activity of AS04, induction of anti-HPV 16 and HPV 18 antibodies and inhibition of major neutralizing epitopes in animal and human subjects, were presented today at the American Association for Cancer Research (AACR) International Conference on Frontiers in Cancer Prevention Research in Baltimore, Maryland, as well as communicated at ECCO 10, the congress of the Federation of European Cancer Societies, in Paris, France.
“In the field of vaccinology, GlaxoSmithKline continues to innovate. GSK has been developing new adjuvant systems for more than a decade. For our cervical cancer vaccine we pursued the objective of inducing a strong immune response and protection that lasts. We are encouraged by an enhanced antibody response we saw with an HPV vaccine formulated with our novel adjuvant,” said Gary Dubin, Vice President, HPV Vaccines, GlaxoSmithKline. Cervical cancer is lifelong concern for women and GlaxoSmithKline is committed to lessening the burden of this disease for women worldwide.
HPV is the leading cause of cervical cancer. Seventy seven percent of all cervical cancer cases are associated with only two oncogenic types, HPV 16 and HPV 18*. GlaxoSmithKline’s cervical cancer vaccine candidate targeting these two oncogenic HPV types is currently undergoing Phase III clinical trials involving more than 28,000 women worldwide.
About the studies
Three separate methods were used to evaluate the ability of an HPV 16/18 L1 vaccine formulated with either the AS04 adjuvant, composed of aluminum plus 3-deacylated monophosphoryl lipid A (MPLTM), or aluminum salt alone to induce an immune response of high magnitude and persistence.
Activation of the immune system by AS04 or aluminum salt alone was assessed in-vitro using the human monocyte cell line U937. Using a common immunology test, an ELISA (Enzyme-Linked Immunosorbent Assay), researchers evaluated the production of TNF-alpha (Tumor Necrosis Factor-alpha) which is a key mediator of immunologic functions. Data demonstrate that AS04 was associated with substantial and greater induction of TNF-alpha production, compared to aluminum salt alone.
In addition, following vaccination with an HPV 16/18 L1 vaccine of mice, monkeys, and women aged 18 to 30, serum samples were evaluated for antibodies to HPV 16 and HPV 18 L1 VLPs. Furthermore, an inhibition ELISA was used for measure of antibodies specifically directed against the major neutralizing sites on HPV 16 and HPV 18, known as V5 and J4 epitopes, respectively. The findings demonstrate that one month following the second or third vaccine doses, GlaxoSmithKline’s investigational cervical cancer vaccine formulated with AS04 induced anti-VLP 16 and 18 antibodies that were substantially higher than with the aluminum salt only formulation. Additionally, higher levels of antibodies directed against key V4 and J5 neutralizing epitopes were induced. Moreover, the higher antibody responses associated with the AS04 formulation persisted for up to at least 3.5 years post-vaccination in human subjects.
About Cervical Cancer
Cervical cancer is a major global health problem, with nearly 500,000 new cases occurring each year worldwide. It is the second most common cancer -- and the third leading cause of cancer deaths -- in women worldwide. In the United States, approximately 10,000 women will develop cervical cancer this year, and nearly 4,000 will die from the disease. HPV is the leading cause of cervical cancer. There are many types of HPV; however, 77 percent of all cervical cancer cases are associated with only two oncogenic types, HPV 16 and HPV 18.*
An estimated 20 million people in the U.S. are currently infected with genital HPV. HPV infection is very common among sexually active people, with an estimated 5.5 million new infections occurring every year in the U.S. In fact, by the age of 50, approximately 80 percent of women will have been infected with HPV. Genital HPV infection is especially common in women under the age of 25. HPV infections are usually transient and generally cause no symptoms. Persistent infection with oncogenic types of HPV may lead to cervical cancer.
Screening for abnormal cervical cells using the Pap smear has significantly reduced the number of cervical cancer cases in the U.S. However, there are nearly three million abnormal Pap smears each year, which may require additional follow-up and treatment. The total healthcare cost to evaluate and treat women with abnormal Pap smears in the U.S. has been estimated at $6 billion annually. In addition, there are personal and social costs associated with abnormal pap tests and cervical cancer -- including emotional distress and anxiety -- which cannot be measured in dollars.
GLAXOSMITHKLINE: A LEADER IN VACCINES
GlaxoSmithKline, with U.S. operations in Philadelphia, PA, and Research Triangle Park, N.C., is one of the world’s leading research-based pharmaceutical and healthcare companies and is committed to improving the quality of human life by enabling people to do more, feel better and live longer.
* Note, 77 percent applies to North America and Australia.
GlaxoSmithKline
CONTACT: Danielle Halstrom of GlaxoSmithKline, +1-919-483-2839; or GinaPozadas of Cohn & Wolfe for GlaxoSmithKline, +1-212-798-9769
