Tobira Therapeutics Announces Positive 24-Week Primary Analysis From Phase 2b Trial of Cenicriviroc in Treatment-Naïve HIV Infection

Results Support Advancement to Phase 3 Registrational Studies

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Tobira Therapeutics today announced positive results from the 24-week primary analysis of Study 202, the Phase 2b study of cenicriviroc (CVC). CVC is a novel, oral, once-daily, dual CCR5/CCR2 inhibitor. Tobira is investigating CVC for the treatment of HIV-1 infected adults with CCR5-tropic virus. This 143-patient, double-blind, double-dummy, randomized, controlled Phase 2b trial (Study 202, NCT01338883) met its primary objective over 24 weeks of treatment. A similar proportion of patients treated with either 100mg or 200mg of once-daily CVC plus Truvada^® (emtricitabine/tenofovir disoproxil fumarate) achieved undetectable HIV viral load (<50c/mL) at week 24 when compared to patients treated with once-daily Sustiva^® (efavirenz) plus Truvada^®. A favorable safety and tolerability profile was observed in CVC-treated patients.

“We are very pleased with the findings of Study 202 and plan to present detailed results at a scientific meeting in the first half of 2013”

“We are very pleased with the findings of Study 202 and plan to present detailed results at a scientific meeting in the first half of 2013,” 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.”

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

About Cenicriviroc

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