Twenty-four-week results published July 7 in the Lancet showed that 62 percent of patients on the DUET-1 combo had complete viral suppression compared to 44 percent on standard
of care, while 56 percent on the DUET-2 monotherapy reached viral undetectability compared with 39 percent on standard of
care. Based on these early results, Tibotec immediately filed for FDA approval of etravarine. Data from a second Tibotec study
were also unveiled. In a gutsy head-to-head trial pitting Prezista against the leading first-line protease inhibitor, Abbott's
Kaletra, in patients with moderate resistance, 70 percent of Prezista patients had undetectable virus after 48 weeks compared
with 61 percent on Kaletra. Pomerantz trumpeted the news as "a home run," and Tibotec was set to be the talk of the high-profile
International AIDS Society annual confab in late July.
In equally Young Turk fashion, Tibotec is dueling it out for "most powerful and durable in the non-nucleoside class" in a
Phase II head-to-head that tests the company's second non-nuke, rilpivirine, against BMS's Sustiva in treatment-naïve patients.
At the 48-week mark in March, the two drugs were neck and neck, with undetectability at about 80 percent. But rilpivirine
has a distinct edge or two over Sustiva: a higher genetic barrier plus none of Sustiva's disturbing side effects (central-nervous-system
havoc and birth defects). In addition, it is a small molecule "perfect for one-pill, once-a-day dosing, and for combining
with other medications in fixed doses," says Pomerantz.
Phase II comparative-drug tests are risky for the challenger and, therefore, rare outside of HIV R&D. But FDA applauds such
real-world results, and is likely to fast-forward rilpivirine's approval.
Tibotec's arrival on the scene with three new drugs, innovative studies, and glowing real-world data has some analysts buzzing.
"If both head-to-head trials succeed for Tibotec, the company will be able to reposition Prezista and rilpivirine as first-line
contenders against the current industry leaders," says Datamonitor's Mansi Shah. "This will shake up the market pretty substantially
in addition to being a major advance for patients." Prezista, in particular, with its resistance-proof power, has a long shot
at even turning the treatment paradigm on its head, allowing for patient-friendly, low-toxic monotherapy, says Ron Camp.
Shah projects that Prezista will hit $850 million in sales by 2015, while rilpivirine's revenues will pass the $700 million
mark and etravarine's, $300 million. These "resistant to resistance" drugs, along with Gilead and BMS's one-a-day combo Atripla
and the new classes of entry, integrase, and maturation inhibitors, are expected to drive the HIV market up from $7.4 to $10.6
billion by 2015—despite the patent expirations of most of the top-selling products. "Tibotec stands to become one of the leading
HIV companies in 10 years' time," says Shah.
The Price of Progress
The acid test of Tibotec's community bona fides came in setting the price for Prezista in 2006.
The pricing of new HIV drugs had come to resemble a game of leap-frog, with the newest hopping over the threshold set by its
predecessor with little regard for its likely therapeutic value. In the protease-inhibitor class, for example, Abbott's Kaletra,
approved in 2000, cost $9,500 a year; BMS's Reyataz, approved in 2003, $10,900; and Boehringer-Ingelheim's Aptivus (tipranavir),
approved in 2005 and widely viewed as underwhelming, $13,600. Tibotec initially announced that it would embrace the model,
pricing Prezista at $18,500 a year, higher even than the priciest HIV drug, Fuzeon (enfuvirtide)—an injectible entry inhibitor
that is many salvage patients' last resort.