Tibotec hopes to win accelerated approval for its experimental protease inhibitor TMC114 in the United States and Europe by the middle of 2006 if drug regulators move quickly to review early data on the drug, the company announced today. TMC114 would initially be licensed for treatment-experienced patients, in the same way as Boehringer-Ingelheim’s tipranavir (Aptivus).
Tibotec also plans to launch an expanded access programme in the autumn of 2005 to enable people running out of treatment options to obtain early access to the drug.
Individuals who have extensive experience of antiretrovirals and need TMC114 to construct a viable HAART regimen will be eligible for the expanded access programme. Individuals will also need to have a CD4 cell count below 100 cells/mm3 and a viral load above 10,000 copies/ml. The drug has yet to enter its phase III clinical trial and the expanded access scheme is dependent upon the approval of regulatory authorities and recruitment to the phase III trial.
The company is pinning its hopes for early approval on phase II trial data, which showed that nearly half of protease-experienced patients who received TMC114 in addition to a background regimen optimised by resistance testing achieved a viral load below 50 copies/ml after 24 weeks, with an average viral load reduction of -1.85log10, probably the most impressive result yet seen when a second-generation boosted protease inhibitor is used in treatment-experienced patients.
Unusually, Tibotec has announced that it will submit these data to win accelerated approval in early 2006, before it has completed phase III trials in Europe and the United States. US approval could follow within less than six months, with European approval shortly behind.
The phase II studies, which were still incomplete when interim findings were presented at February’s Twelfth Conference on Retroviruses and Opportunistic Infections, compared three doses of TMC114 plus ritonavir with a control group in which patients received a boosted protease inhibitor selected by the study investigators after resistance testing. The study showed that the highest dose of TMC114 (600mg boosted by 100mg of ritonavir, twice daily) performed best, and this dose is now being studied in phase III studies in treatment-experienced and treatment-naïve patients.