Boehringer Ingelheim has won full US Food and Drug Administration clearance to market its AIDS therapy Aptivus (tipranavir).

Aptivus, a protease inhibitor that works by inhibiting the enzyme needed to complete the HIV replication process, was approved under the accelerated approval process in 2005, which is designed to allow therapies for serious or life-threatening illnesses that are deemed to provide meaningful benefit to patients over existing treatments faster access to the market.

Following its traditional approval, Aptivus, co-administered with 200mg of ritonavir, is indicated for combination antiretroviral treatment of HIV-1 infected adult patients who are treatment-experienced and infected with HIV-1 strains resistant to more than one protease inhibitor.

The green light is based largely on 48-week analyses of the Phase III pivotal clinical studies RESIST (Randomized Evaluation of Strategic Intervention in Multi-Drug ReSistant Patients with Tipranavir), which showed that more than twice the percentage of patients (33.8%) treated with a combination of Aptivus and ritonavir achieved a treatment response compared to those patients treated with a comparator PI regimen (14.9%), and that more 30.3% of patients in the Aptivus/r arm achieved a viral load of less than 400 copies/mL compared to 13.6% in the control group.

“Data show that Aptivus/r may provide treatment-experienced HIV patients with an effective treatment option through nearly one year of therapy,” explained Dr Daniel Kuritzkes, associate professor of medicine at Harvard Medical School and director of AIDS research at the Brigham and Women`s Hospital in Boston. “Furthermore,” he said, “longer-term safety data are now available for physician and patient consideration.”

SPRING trial

Earlier this year, the company commenced enrolment of patients in a Phase IIIb trial of Aptivus to assess its efficacy across a wide range of race and gender.

The SPRING project “will be one of the largest racially and gender diverse international studies of highly treatment-experienced HIV-1 infected patients”, the German-headquartered drugmaker said at the time, noting that it will examine the safety, efficacy and pharmacokinetics of Aptivus in a racially diverse group of 200 female and 200 male treatment-experienced patients across eight countries (at 72 sites) in three continents.

Clinical trials have shown that the efficacy of antiretroviral treatments may vary across races and genders, and SPRING is designed to further examine Aptivus’ utility in a diverse subset of patients.