LONDON—ViiV Healthcare, a global specialist HIV company that is majority owned by GlaxoSmithKline, with Pfizer Inc. and Shionogi Limited as shareholders, recently presented positive results from the LATTE-2 study at the Conference on Retroviruses and Opportunistic Infections in Boston. LATTE-2 is a Phase 2b, open-label study investigating the long-acting, injectable formulations of cabotegravir (ViiV Healthcare) and rilpivirine (Janssen Sciences Ireland) as a two-drug treatment for patients with HIV-1 infection who already achieved HIV viral suppression with a three-drug oral regimen of cabotegravir plus two nucleoside reverse transcriptase inhibitors (NRTIs). The primary endpoint evaluated antiviral activity and safety through 32 weeks of maintenance treatment.
Following 32 weeks of maintenance treatment, viral suppression rates for the two drug regimen dosed every eight weeks or every four weeks were comparable to the rate observed in patients continuing with a three-drug oral regimen. One patient in the eight-week dosing group and one patient in the oral regimen group met protocol-defined virologic failure criteria; neither patient had evidence of resistance at failure. The most common drug-related adverse event reported by patients receiving injectable study medication was injection site pain, mostly mild or moderate in severity.
Dr. John C Pottage, Jr., chief scientific and medical officer for ViiV, commented, “There continues to be a need for new HIV medicines, including those that could offer more flexible dosing regimens for people living with HIV. The LATTE-2 study results provide the first evidence that a long-acting two-drug injectable regimen may offer an alternative to daily, oral three-drug therapy for people who have achieved viral suppression. We are aiming to commence Phase 3 studies this year.”
During the maintenance period, the most commonly reported adverse events not related to injection site reactions for the injectable treatment groups were nasopharyngitis, headache and diarrhea. For patients randomized to oral treatment, the most common adverse events during the maintenance period were similar. Serious adverse events occurred in 6 percent of patients receiving injectable treatment (one drug-related) and 5 percent of patients receiving oral cabotegravir (none drug-related). One patient in the eight-week injectable treatment group died due to an event unrelated to study drug (seizure). Nine patients withdrew from the study due to adverse events. Lab abnormalities that emerged during the maintenance phase (Grade 3 severity) occurred in 16 perdent of injectable treatment patients and 14 percent of oral treatment patients through week 32.
LATTE-2 is an ongoing international multicenter, parallel group, open-label study that included 309 HIV-infected adults who had not received prior antiretroviral treatment. Enrolled patients were suppressed virologically during a 20-week induction period with daily oral cabotegravir plus two NRTIs and subsequently randomized to one of three study arms in the maintenance period: intramuscular cabotegravir long-acting formulation plus rilpivirine long-acting formulation every four weeks; intramuscular cabotegravir long-acting formulation plus rilpivirine long-acting formulation every eight weeks; or oral cabotegravir plus two NRTIs. The primary endpoint evaluated antiviral activity and safety through 32 weeks of maintenance treatment, and the study will continue up to 104 weeks of treatment.
