Thursday, April 02, 2009

Vaccine Season: A Rush of Good News

Maybe the Centers for Disease Control should hold more national immunization conferences.

CDC opened the 43rd annual conference on Monday, March 30 in Dallas and lo-and-behold two major vaccine marketers announced the filing of major licensing applications with the Food & Drug Administration: GlaxoSmithKline refiled its application for the bi-valent HPV vaccine, Cervarix and Wyeth filed for the second generation pneumoccocal conjugate vaccine, Prevnar 13.

FDA jumped right into the good news mode: the agency announced the first U.S. approval for an Intercell product: Ixiaro for Japanese encephalitis virus.

If getting together 1,500 people from the vaccine community stimulates this type of activity, CDC should hold the meetings monthly.

None of the events was a big surprise; yet each is an interesting story. The Cervarix resubmission completes a process that began following the rejection of its initial application to FDA at the end of 2007. The pivotal trial for the U.S. application remains the same from the initial application which was based on interim data. The new application was filed almost exactly two years to the day from the initial submission to FDA. The completed trial HPV-008 contains data on 18,600 females 15-25. With approvals in 90 other countries, the firm has an ever-expanding database on use of the vaccine around the world. Conservatively, the firm is still citing clinical trial data on approximately 30,000 females 10-55.

CDC’s Advisory Committee on Immunization Practices (ACIP) which makes the key use recommendation for a new vaccine is preparing to receive the GSK product at its upcoming meetings in June and October, with the vote on a recommendation most likely in October. That means that Cervarix will miss another back-to-school check-up season that is important to a U.S. launch.

The FDA review of Cervarix, however, has faded in commercial importance to GSK: Merck’s lead in the effort to vaccinate adolescent girls has taken away much of the initial market opportunity in the U.S. But the approval still remains important for the company and for the vaccine industry as the leading edge of the effort to get U.S. approval for new adjuvants.

How GSK convinces FDA that the adjuvant contributes to the vaccine efficacy without raising safety issues will set an important precedent for the wave of adjuvanted products building up in pipelines. In GSK’s case, the first adjuvant is a combination of alum and monophosphoryl lipid A (MPL). GSK calls the adjuvant AS04; it is part of a broader strategy based on a series of adjuvants.

For Wyeth, the announcement of the Prevnar-13 pediatric application starts the final process for the important next generation of its pneumococcal conjugate to try to expand its flattening but important U.S. business (stuck at about $1.2 billion) and with key valents for the developing world market.

A pending World Bank Advanced Purchase Commitment – a major part of the effort to collect funding to pay for the vaccine in developing nations -- calls for pneumococcal vaccines to address serotypes 1 and 5, which are part of the six additional serotypes in Prevnar-13.

Wyeth emphasizes that another of the new serotypes (19A) will reinforce its leading U.S. position by addressing the serotype that has emerged as the most prominent threat in the wake of the success of the first vaccine. Wyeth began its international filings for Prevnar-13 at the end of 2008. In overseas markets, it is trying to prevent an opening to develop for GSK’s 10-valent Synflorix, which has just reached the European Commission recommendation for approval.

The Intercell approval of the Japanese encephalitis vaccine announces the arrival of a new boutique vaccine development firm and indicates that there is still room in the consolidating vaccine field for small firms to find niches and partnership roles.

Intercell has significant partner arrangements with several of the major vaccine marketers: Merck for staphylococcus aureus, Novartis has options on a hepatitis C vaccine, an adjuvant and an option on a pseudomonas aeruginosa vaccine, Sanofi-Pasteur on an undisclosed bacterial indication. Intercell has an early stage pneumococcal vaccine in development for the non-governmental organization PATH that is part of the effort to find a long-range alternative to the the expensive Wyeth and GSK vaccines.

Novartis and Australia’s CSL will help sell Ixiaro to the travelers market for people going to Asia. That’s an untapped market: Intercell is setting a modest goal of getting 4% of the western travelers to affected areas. That goal could carve out a nice starting point for the Austrian firm.

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