FDA panel OKs Pfizer's Selzentry for broader us in HIV naive patients, but drug criticized for its cost

The US Food and Drug Administration's Antiviral Drugs Advisory Committee has voted (10 to four) to recommend the approval of global drug behemoth Pfizer's Selzentry (maraviroc) tablets for use in treatment-naive adult patients with CCR5-tropic HIV-1 virus as part of combination therapy, but the moved was criticized by an AIDS activitist group because of the drug's cost.

'Pfizer is pleased that the Committee has recognized the effectiveness and safety profile of maraviroc in patients who are starting HIV therapy,' said Howard Mayer, Pfizer's executive director and disease area leader, antivirals. 'Today's discussion marks an important step in expanding available treatment options for patients with HIV infection and we look forward to working with the FDA to further address the points raised by the panel,' he added.

FDA reviewers raised concerns about higher levels of viral activity in patients taking Selzentry compared with Sustiva (efavirenz). About 32% of patients did not adequately respond to Pfizer's drug, compared with 24 percent of patients taking the alternative. Selzentry had $46 million in sales last year, according to Pfizer. However, Sustiva from Bristol-Myers Squibb, a once-daily HIV drug approved by the USA in 1998, generated $1.15 billion for the New York-based drug major

Selzentry was granted accelerated approval in August 2007 and full approval in November 2008 by the FDA for use in treatment-experienced adult patients with only CCR5-tropic HIV-1 virus in combination with other antiretroviral therapies.

In making its decision, the Advisory Committee reviewed 48- and 96-week efficacy and safety data from the ongoing Phase III MERIT (Maraviroc versus Efavirenz Regimens as Initial Therapy) trial and MERIT ES (analysis of the MERIT study with the enhanced sensitivity Trofile assay).

Results of MERIT at 48-weeks showed that Selzentry plus Combivir (zidovudine/lamivudine) was as effective as Sustiva) plus zidovudine/lamivudine at reducing viral load for the co-primary endpoint of <400 copies/ml, but did not show non-inferiority for the co-primary endpoint of ><50 copies/ml at 48-weeks. safety results at 96-weeks showed that among those patients who remained on therapy, less than half the number of malignancies were observed in those taking selzentry compared to those taking efavirenz. additionally, no new safety signals were identified in association with selzentry at 96-weeks. the most frequently reported adverse events were nausea, headache, dizziness, diarrhea, fatigue, upper respiratory tract infection, and vomiting. patients were screened into the study using the original trofile assay which is no longer available. >

At the end of 2006, an estimated 1.1 million people in the U.S. were living with HIV infection. The Centers for Disease Control and Prevention (CDC) estimates that in 2006 approximately 56,300 people were newly infected with HIV in the U.S. (the most recent year that data are available).

Selzentry 'poised to be most expensive first-line AIDS drug'

Responding to the announcement, the AIDS Healthcare Foundation (AHF) strongly criticized Pfizer for its current pricing of the drug at an Average Wholesale Price (AWP) of $13,767 per-patient per- ear which, if this price remains when use is expanded, would make it the most expensive first-line AIDS drug on the market.

Selzentry was originally priced at $12,528 per-patient per-year. In just two years, the price for the drug, which must be taken with at least two other AIDS drugs, has increased by nearly 10%, the AHF argues.

"In this time of growing national concern over ballooning health care costs, it is simply criminal for Pfizer to continue to price Selzentry at the salvage therapy rate, especially now that the market for the drug will be vastly expanded by the FDA's likely upcoming approval of the drug for first-line use," said Michael Weinstein, president of the AIDS. "Government programs such as AIDS Drug Assistance Programs and Medicaid are likely to be the largest purchaser of Selzentry. Where exactly does the burden of Pfizer's price-gouging fall? On the taxpayers. And for what reason? So that the largest pharmaceutical company in the world, Pfizer, can make just a little more profit - while bankrupting government programs already hurting for funds as they work to ensure that Americans living with HIV/AIDS receive the lifesaving treatment they need,' he continued.

'While any new HIV/AIDS drug on the market is welcome, we urge Pfizer to use restraint and to lower the price of Selzentry immediately upon FDA approval for this expanded use," said Mr Weinstein.

An estimated 1.2 million people in the USA are living with HIV/AIDS. As a result of antiretroviral treatment, many more people are living longer, and a greater burden has been put on the health care system, including several of the federally funded, state-run AIDS Drug Assistance Programs (ADAP) nationwide, the Foundation argues. Funding for AIDS care has been largely flat-funded or saw only minor funding in recent years - increases which are not proportional to the need, nor able to support inflated pharmaceutical prices, the AHF said.