In the ongoing RESIST trials, Aptivus demonstrated superior virologic and immunologic responses versus a comparator group of protease inhibitors in highly treatment-experienced patients through 96 weeks of therapy (p<0.001).1 The POTENT study will be the first head-to-head study comparing Aptivus to another protease inhibitor developed specifically for treatment-experienced patients with HIV resistant to multiple agents in the protease inhibitor class.
"Treatment-experienced patients need active treatment options to help achieve and maintain undetectable viral load. Tipranavir and darunavir are important antiretroviral agents for these patients and there is much to learn regarding their respective roles in treatment. POTENT is an important study because it will help provide physicians and patients with this information to guide future treatment choices," said Laurent Cotte, M.D., Hepatology/AIDS Unit, Hotel-Dieu Hospital, Lyon, France.
The POTENT (PrOspecTive EvaluatioN of Tipranavir vs. Darunavir in Treatment Experienced Patients) study will be a Phase IV, open-label, multinational, randomised study of patients previously treated with three classes of antiretrovirals, with a minimum of three months duration in each class, and documented resistance to more than one protease inhibitor. Virologic response will be defined as viral load of less than 50 copies/mL. Patients will be randomised to receive 500 mg of Aptivus boosted with 200 mg of ritonavir twice daily or 600mg of darunavir boosted with 100 mg of ritonavir twice daily. Both agents will be administered with an optimized background regimen, which may include certain investigational agents. Patients will be observed for a period of 48 weeks.
"Boehringer Ingelheim is committed to the ongoing study of Aptivus, and anticipates that POTENT will reinforce the therapeutic benefits of Aptivus for HIV-positive treatment-experienced patients. We expect results from the study will be available in 2010," said Dr. Andreas Barner, Vice-Chairman, Board of Managing Directors and Head of Corporate Board Division Pharma Research, Development and Medicine, Boehringer Ingelheim.
The POTENT study will enroll 800 patients in more than 150 sites across 15 countries. HIV-1 infected male and female patients aged 18 years and older will have been on their current failing protease inhibitor-containing regimen for at least 8 weeks, will have a CD4+ cell count of ≥50 cells/mmÂ³ and a viral load count of ≥1000 copies/mL. Patients who have had a prior AIDS-defining event will be eligible as long as the event has resolved for at least twelve weeks before screening, excepting patients with a history of progressive multifocal leukoencephalopathy, visceral Kaposi`s sarcoma, and/or any malignancy.
Aptivus is a new non-peptidic protease inhibitor which works by inhibiting the viral protease, an enzyme needed to complete the HIV replication process. It is approved for combination antiretroviral treatment of HIV-1 infected adults that are highly pre-treated with virus resistant to multiple protease inhibitors.
Based on available clinical and in vitro data, Aptivus is active against most strains of HIV-1 that are resistant to commercially available protease inhibitors.
Currently, phase II and III studies in paediatric and other populations are fully enrolled and ongoing.
The most commonly reported side effects of at least moderate intensity in patients enrolled in the RESIST studies taking Aptivus are gastrointestinal, including diarrhoea, nausea, vomiting and abdominal pain. Fever, fatigue, headache, bronchitis, depression and rash also occurred. Gastrointestinal symptom disorders and elevated transaminase, cholesterol and triglycerides were more frequent in the Aptivus arm than in the comparator-ritonavir group but necessitated discontinuation of treatment in a minority of cases.
Aptivus boosted with low-dose ritonavir has been associated with reports of hepatic adverse events, which have included some fatalities. These have generally occurred in patients with advanced HIV disease taking multiple concomitant medications. Extra vigilance is warranted in patients with chronic hepatitis B or hepatitis C co-infection, as these patients have an increased risk of liver toxicity. The most common moderate to severe laboratory abnormalities were elevated liver enzymes and elevated lipid levels. Most laboratory abnormalities were asymptomatic and most patients were successfully treated without discontinuation.
Aptivus-containing HAART regimens have been associated with reports of both fatal and non-fatal intracranial hemorrhage (ICH) in some highly treatment-experienced patients. Caution should be used when prescribing Aptivus/r in patients who may be at risk of increased bleeding or who are receiving medications known to increase the risk of bleeding.
Aptivus does not cure HIV infection/AIDS or prevent the transmission of HIV to others. Patients may continue to develop opportunistic infections and other complications associated with HIV disease.
Apart from the EU, Aptivus has received U.S. marketing authorization by the FDA and was launched there in June 2005. Additional marketing authorizations from different countries have been received or are expected.
About Boehringer Ingelheim
Boehringer Ingelheim is committed to the research and development of novel antiretroviral agents. Apart from Aptivus® (tipranavir), Viramune® (nevirapine) is a product of original research done at Boehringer Ingelheim. Viramune was the first member of the non-nucleoside reverse transcriptase inhibitor (NNRTI) class of anti-HIV drugs on the market. The company is involved in basic research in that area and is committed to improving HIV therapy by providing physicians and patients with innovative antiretroviral treatment options.
Boehringer Ingelheim is actively conducting clinical trial programs to further evaluate Aptivus and Viramune for the treatment of HIV-1 infection. The Aptivus clinical trial program is comprised of ongoing and planned studies in more than 1,400 treatment-experienced patients. In addition to the POTENT study, Boehringer Ingelheim is also conducting the SPRING trial to examine the benefits of Aptivus in an ethnically and racially diverse highly treatment-experienced patient population. The VIRAMUNE clinical trial program includes the ArTEN trial, which aims to compare the efficacy and safety of Viramune dosed once or twice daily versus atazanavir boosted with ritonavir in HIV-positive antiretroviral-naÃ¯ve patients. For further information, please visit www.boehringer-ingelheim.com