Theratechnologies Announces New Data from the Pivotal Phase III Trial of HIV Monoclonal Antibody and Long-Acting Investigational Antiretroviral Ibalizumab

MONTRÉAL, QUÉBEC--(Marketwired - Feb. 14, 2017) - Theratechnologies Inc. (Theratechnologies) (TSX:TH) announced today that additional secondary efficacy and safety endpoint results from the 24-week ibalizumab Phase III trial, TMB-301, were presented at a late-breaker session at the Conference on Retroviruses and Opportunistic Infections (CROI) 2017. Preliminary secondary efficacy and safety endpoint results were announced on November 10, 2016.

The new data showed that patients with multidrug resistant (MDR) HIV-1 infection experienced a mean increase in CD4⁺ T cell of 48 cells/µL after 24 weeks of treatment with ibalizumab plus an optimized background regimen (OBR). These data supplement previously reported findings, where 83% of patients achieved a ≥ 0.5 log₁₀ decrease in viral load from baseline seven days after the single loading dose of 2000 mg of ibalizumab (primary endpoint) and a mean reduction in viral load of 1.6 log₁₀ over the 24 week treatment period with more than 48% of patients experiencing a viral load reduction of more than 2.0 log₁₀.

"CD4⁺ T cells play an important role in protecting the body from infection. The higher the CD4⁺ T cell count, the better able you are to fight HIV and other infections," said Dr. Brinda Emu, Assistant Professor of Medicine, Infectious Diseases, Yale School of Medicine, New Haven, CT. "This meaningful increase in CD4⁺ T cell counts is particularly important for patients with multidrug resistant virus, as they often have the most advanced disease. These data suggest that for these patients, ibalizumab could be an important new treatment option," added Dr. Emu.

Patients enrolled in this Phase III trial experienced a significant decrease in viral load after receiving a single loading dose of ibalizumab 2,000 mg intravenously (IV) in addition to their failing ART (or no therapy). Viral load decreases were maintained during the 24-week trial. At the end of the treatment period, the proportion of study participants with undetectable viral load (HIV-1 <50 copies/mL) was 43% (mean viral load reduction of 3.1 log₁₀) and 50% of patients had a viral load lower than 200 copies/mL.

Total CD4⁺ T cell increases varied according to baseline levels of CD4⁺ T cells. Patients with baseline CD4⁺ T cells lower than 50 cells/µL (17 patients) had an increase of 9 cells/µL, those with CD4⁺ T cells between 50 and 200 cells/µL (10 patients) had an increase of 75 cells/µL and those with CD4⁺ T cells higher than 200 cells/µL (13 patients) had an increase of 78 cells/µL. Similar efficacy was observed, in a subgroup of 17 patients infected with HIV-1 that was resistant to all FDA approved ART and for whom the only other active agent that could be included in the OBR was another investigational drug.