SOUTH SAN FRANCISCO, Calif. -- Tobira Therapeutics presented positive results from the Phase 2b clinical trial (Study 202) of cenicriviroc (CVC) today at the 20th Conference on Retroviruses and Opportunistic Infections (CROI 2013). CVC is a novel, oral, once-daily, dual CCR5/CCR2 inhibitor in clinical development for the treatment of HIV infection.
Study 202 is a randomized, double-blind, double-dummy, dose-finding, controlled study that enrolled 143 HIV-1 infected patients with CCR5-tropic HIV infection. At week 24, 100mg or 200mg of once-daily CVC plus Truvada® (emtricitabine/tenofovir disoproxil fumarate) demonstrated similar virologic success rates (76% and 73%) compared to once-daily Sustiva® (efavirenz or EFV) plus Truvada (71%). A favorable safety and tolerability profile was observed in CVC-treated patients. In addition, a significant decrease in monocyte activation, measured by reduction in sCD14 levels, was seen in CVC-treated patients. The complete week 24 results from Study 202 were presented as a Late Breaker Abstract Presentation by Joseph C. Gathe, MD during the session titled “New Agents and New Insights” in a talk titled “Week 24 Primary Analysis of Cenicriviroc vs Efavirenz, in Combination with FTC/TDF, in Treatment-naïve HIV-1 Infected Adults with CCR5-tropic Virus,” (Abstract 106LB).
“In this study CVC showed compelling antiviral activity and favorable safety when compared to the current standard of care,” said Dr. Gathe. “Based on these positive data, CVC has the potential to become an important addition to novel HIV treatment strategies.”
“The promising data generated by Study 202 reinforce our resolve to make CVC a key component in the future treatment of HIV,” said Andrew Hindman, Tobira’s President and Chief Executive Officer. “Based on these data, we are actively planning for the initiation of Phase 3 registrational studies of CVC, including fixed-dose combinations and complete single-tablet regimens containing CVC.”
Study 202 Result Highlights: At the primary endpoint of 24 weeks, the percentage of patients in the 100mg and 200mg CVC study arms achieving virologic success, defined as HIV viral load< 50 copies/mL, was 76% and 73%, respectively compared to 71% in the EFV arm. Cenicriviroc was well tolerated and lower rates of adverse events were observed in the CVC arms when compared to the EFV arm. LDL cholesterol levels decreased among patients receiving CVC, while both LDL and HDL cholesterol levels increased among patients receiving EFV. Anti-inflammatory markers correlating to the CCR2 ligand (MCP-1) increased in a dose-dependent manner among patients who received CVC. Finally, levels of sCD14, a marker of monocyte activation and an independent predictor of mortality in HIV infection, decreased over the course of the study for CVC-treated subjects, but increased for EFV-treated subjects.
Study 202 Design: Study 202 is a double-blind, double-dummy, randomized, controlled Phase 2b trial, evaluating once-daily doses of CVC 100mg or 200mg compared to once-daily Sustiva® (efavirenz), each in combination with open-label Truvada® (emtricitabine/tenofovir disoproxil fumarate). The study enrolled a total of 143 treatment-naïve, HIV-1 infected adults with CCR5-tropic virus. Patients with CCR5-tropic virus represent approximately 80% of the treatment-naïve HIV-infected population. The primary objective of this trial is to determine the efficacy and safety of CVC when compared to efavirenz, both as part of combination HIV therapy. Additionally, the trial assesses changes in biomarkers associated with inflammation, metabolic parameters, and immune function. The study will continue for a total duration of 48 weeks for further evaluation of efficacy and safety.
Phase 3 Development Strategy: Based on the results of Study 202, Tobira is preparing for CVC’s Phase 3 registrational program. Tobira plans to conduct two, randomized, controlled, double-blinded, double-dummy, Phase 3 trials, each in approximately 750 HIV-1 infected adults with CCR5-tropic HIV virus. These trials will evaluate efficacy and safety of CVC-containing combination regimens compared to treatment guideline-preferred first-line treatment options. The trials will be designed with a 48-week primary analysis to support global regulatory filings, and will continue for 96-weeks in the final analysis. The trials will also assess the effect of CVC on inflammatory and metabolic comorbidities often associated with chronic HIV-1 infection. Patients with HIV infection, even those well-controlled on antiretroviral therapy, experience these diseases earlier and at higher rates than uninfected individuals.1
Cenicriviroc (CVC) is a novel, oral, once-daily, fixed-dose combinable, dual inhibitor of chemokine receptors CCR5 and CCR2 being developed for the treatment of HIV-1 infection. CVC was designed to bind and block two cellular chemokine receptors: CCR5 and CCR2. The CCR5 receptor is a key avenue for entry of HIV into human T-cells. CCR2 is involved in monocyte-related immune activation, which is implicated in several inflammation-mediated diseases. Tobira’s HIV development program evaluates CVC as a single-agent tablet and in fixed-dose combination tablets with other HIV antiretrovirals, for use in complete regimens for treatment of HIV infection. Annually, the U.S. CDC and UNAIDS estimate 47,500 and 2.5 million new HIV infections occur in the U.S. and globally, respectively.
About Tobira Therapeutics
Tobira Therapeutics is a privately held biopharmaceutical company developing innovative therapies for treatment of HIV infection. The company’s lead development candidate is cenicriviroc (CVC), a novel, oral, once-daily, fixed-dose combinable, dual inhibitor of chemokine receptors CCR5 and CCR2. Tobira has financial support from a syndicate of leading life science investors including Domain Associates, Frazier Healthcare Ventures, Montreux Equity Partners, Novo Ventures and Canaan Partners. Learn more at www.TobiraTherapeutics.com.
1 Volberding and Deeks, Antiretroviral therapy and management of HIV infection. Lancet Vol. 376 (July 3, 2010), and The Journal of Infectious Diseases 2012:205