The FINANCIAL — ViiV Healthcare, the global specialist HIV company majority owned by GSK, with Pfizer Inc. and Shionogi Limited as shareholders, on February 23 presented positive results from the LATTE-2 study at the Conference on Retroviruses and Opportunistic Infections (CROI) in Boston. Headline results were announced in November 2015.
LATTE-2 is a phase IIb, open label study investigating the long-acting, injectable formulations of cabotegravir (ViiV Healthcare) and rilpivirine (Janssen Sciences Ireland UC) as a two-drug treatment for patients with HIV-1 infection who had 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, according to GSK.
Following 32 weeks of maintenance treatment, viral suppression rates (%) for the two drug regimen dosed every eight weeks (95%) or every four weeks (94%) were comparable to the rate observed in patients continuing with a three drug oral regimen (91%). 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 (92%), most of which were mild (82%) or moderate (17%) in severity.
John C Pottage, Jr., MD, Chief Scientific and Medical Officer, ViiV Healthcare 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 III studies this year.”
Adverse Events in LATTE-2
During the maintenance period, the most commonly reported adverse events not related to injection site reactions for the injectable treatment groups were nasopharyngitis (20%), headache (14%) and diarrhoea (12%). For patients randomised to oral treatment, the most common adverse events during the maintenance period were nasopharyngitis (25%), headache (7%), and diarrhoea (5%). Serious adverse events occurred in 6% of patients receiving injectable treatment (one drug-related) and 5% 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% of injectable treatment patients and 14% of oral treatment patients through week 32.
LATTE-2 (NCT02120352) is an ongoing international multicentre, parallel group, open-label study that included 309 HIV infected adults who had not received prior anti-retroviral treatment. Enrolled patients were suppressed virologically (HIV-1 RNA <50 c/mL) during a 20-week induction period with daily oral cabotegravir (30mg) + 2 NRTIs and subsequently randomised to one of three study arms in the maintenance period: intramuscular cabotegravir long acting formulation (400mg) + rilpivirine long acting formulation (600 mg) every four weeks; intramuscular cabotegravir long acting formulation (600mg) + rilpivirine long acting formulation (900mg) every eight weeks; or oral cabotegravir (30mg) + 2 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.