Global Access for Pfizer's New HIV Drug

With Pfizer's first-in-class HIV drug set to launch next month, the company looks to be sitting pretty in the novel entry-inhibitor niche. Maraviroc, which blocks the most common pathway HIV uses to infect cells, will offer patients with resistant virus a potent treatment option. And forecasters predict that the drug, which will be branded Celsentri, will put a cool $500 million in Pfizer's pocket come 2011--not bad, since the HIV market is valued at about $8 billion.

And thanks to Pfizer's worldwide expanded-access program (EAP), people with HIV are already clamoring for the drug. EAPs, which offer free drugs in exchange for patient data, are fast becoming necessary marketing tools, especially in patient groups with life-threatening diseases and limited healthcare resources. Merck recently set up an EAP for its integrase inhibitor Isentress (raltegravir), and Tibotec launched an EAP prior to the 2006 approval of Prezista (darunavir). "EAPs are quite important in getting the word out about these new drugs," said Datamonitor infectious-disease analyst Mansi Shah.

That's especially true in Pfizer's case. Both GlaxoSmithKline and Schering-Plough had CCR5 inhibitors in their pipelines, which may have sent the juggernaut into a panic. Pfizer ex-VP-turned-whistleblower-blogger Peter Rost claims that the company slipped to the illegal side by using its sales force to recruit new subjects and access sites. But neither FDA nor the mainstream media has shown any interest in the charge from the oft-charging Rost. Meanwhile, Schering-Plough's entry inhibitor vicriviroc has not yet entered Phase III testing--though it'll do so shortly--and no one's seen hide nor hair of Glaxo's CCR5 inhibitor since the company halted its Phase III trial of aplaviroc in late 2005. This currently leaves maraviroc the sole hope for some HIV patients--and the sole beneficiary of the CCR5-antagonist market.

A notoriously mutable virus, HIV sooner or later renders virtually all 27 HIV available drugs powerless. "There will always be a need for new HIV drugs," Shah said. "So many patients now are resistant to all the other drugs out there, there's a constant need that has to be met." These experimental drugs might take several years to complete Phase III trials, but with EAPs, she added, more patients can receive drugs that might work.

In addition, the conventional consumer-push strategy falls short for serious diseases requiring complex--often combination--treatment. "With oncology drugs and HIV drugs, you get a lot less direct-to-consumer advertising," said Elgar Peerschke, global healthcare head of Bain & Co. "You don't want to put false hopes out there for everyone." He added that HIV has strong patient advocacy groups, and that companies are often better served by reaching out to these groups and educating them--though with five classes of competing drugs, just stating the facts isn't enough. "Now, you need to have a posture, a message," Peerschke said.

But while EAPs can be a godsend to patients, they can pose a significant risk to companies. While AIDS advocates argue that the strict medical criteria of EAPs unfairly exclude patients who need the drug, Peerschke noted that too many subjects can make the study go bust.

"You need to have control of the study," Peerschke said. "The more people you take in, the more diverse the conditions, the harder it is to interpret the results."

Balance, then, is the key. But besides stabilizing the subject pool while being sensitive to patients' needs, companies also have to keep their sales reps cutting-edge smart, and with HIV research and drug development evolving almost as quickly as the virus, that can be tough.

"Companies are finding it increasingly difficult to keep their sales force up-to-date," Peerschke said. "But with most physicians in the field being investigators, that's something they have to do."

This story has been corrected to remove an error.