London, 17 November 2020?? ViiV Healthcare, the global specialist HIV company majority owned by GlaxoSmithKline plc (?GSK?), with Pfizer Inc. and Shionogi Limited as shareholders, today announced that the US Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation for long-acting, injectable cabotegravir for HIV pre-exposure prophylaxis (PrEP).

The Breakthrough Therapy Designation was based on efficacy and safety results from HPTN 083, a phase IIb/III randomised, multicentre, double-blind, clinical trial that compared long-acting, injectable cabotegravir to daily oral emtricitabine/tenofovir disoproxil fumarate 200 mg and 300 mg (FTC/TDF) for HIV prevention among men who have sex with men and transgender women who have sex with men.

Final analysis of HPTN 083 showed the superiority of long-acting cabotegravir, which was 66% more effective at preventing HIV when compared to daily oral FTC/TDF tablets. This translated to an HIV incidence rate of 0.41% in the cabotegravir group (95% confidence interval [CI] 0.22%-0.69%) and 1.22% in the FTC/TDF group (95% CI 0.87%-1.67%) in a study population of 4,566. The results of HPTN 083?were presented at the?23rd?International AIDS Conference (AIDS 2020)?in July. The blinded phase of HPTN 084, a partner HIV prevention study in sub-Saharan African women, was stopped earlier this month based upon recommendation of the independent data safety monitoring board (DSMB) following?demonstration that long-acting cabotegravir was superior to oral FTC/TDF tablets. ViiV Healthcare plans to use the data from both HPTN studies for future regulatory submissions.

The Breakthrough Therapy Designation is intended to facilitate the development and expedite the review of drugs that address serious or life-threatening medical conditions. The criteria for Breakthrough Therapy Designation require preliminary clinical evidence that demonstrates a drug may have substantial improvement on at least one clinically significant endpoint over available therapies. The Breakthrough Therapy Designation means closer and more frequent collaboration with the FDA to discuss the drug's development plan and ensure collection of appropriate data needed to support its approval.

Kimberly Smith, M.D., MPH, Head of Research & Development at ViiV Healthcare,?said: ?New medicines that decrease the risk of HIV acquisition in at-risk populations are an essential tool to help us end the global HIV epidemic. Our data from the HPTN 083 and 084 studies show that long-acting cabotegravir is superior to daily oral FTC/TDF tablets for HIV prevention. We are looking forward to working closely with the FDA to make this prevention option available to people at risk of acquiring HIV.?

HIV continues to be a global public health crisis, with an estimated 38 million people living with HIV and 1.7 million new cases of HIV at the end of 2019. Advancements in research and development have identified new approaches to HIV treatment and prevention, such as long-acting cabotegravir. Long-acting cabotegravir has not been approved or licensed anywhere in the world for use in HIV prevention.

About HPTN 083 (NCT02720094) The HPTN 083 study is a phase IIb/III double blind study designed to evaluate the safety and efficacy of long-acting injectable cabotegravir for HIV prevention administered every eight weeks compared to daily oral FTC/TDF tablets (200 mg/300 mg). Each participant was to receive a maximum of three years of blinded study medication. The study opened to enrolment in November 2016. HPTN 083 was conducted in approximately 4,566 men who have sex with men and transgender women who have sex with men at research centres in Argentina, Brazil, Peru, United States, South Africa, Thailand and Vietnam.

For further information on HPTN 083 please?see?https://clinicaltrials.gov/ct2/show/NCT02720094.

About HPTN 084 (NCT03164564) The HPTN 084 study is a phase III double blind safety and efficacy study designed to evaluate the safety and efficacy of the long-acting injectable cabotegravir for HIV prevention administered every eight weeks compared to daily oral FTC/TDF tablets (200 mg/300 mg) in 3,223 women who are at increased risk of HIV acquisition. HPTN 084 opened to enrolment in November 2017 and is being conducted at research centres in Botswana, Kenya, Malawi, South Africa, Eswatini, Uganda and Zimbabwe.

For further information please see?https://clinicaltrials.gov/ct2/show/NCT03164564.

About HIV Prevention Trials Network (HPTN) The HIV Prevention Trials Network (HPTN) is a worldwide collaborative clinical trials network that brings together investigators, ethicists, community members and other partners to develop and test the safety and efficacy of interventions designed to prevent the acquisition and transmission of HIV. The National Institutes of Health (NIH), the National Institute of Mental Health (NIMH) and the National Institute on Drug Abuse (NIDA) co-fund the HPTN. The HPTN has collaborated with more than 85 clinical research sites in 19 countries to evaluate new HIV prevention interventions and strategies in populations that bear a disproportionate burden of infection. The HPTN research agenda ? more than 50 trials ongoing or completed with over 161,000 participants enrolled and evaluated ? is focused primarily on the use of antiretroviral drugs (antiretroviral therapy and pre-exposure prophylaxis); and integrated strategies including interventions for substance abuse, particularly injection drug use; behavioural risk reduction interventions and structural interventions. For more information, visit?hptn.org.

About ViiV Healthcare ViiV Healthcare is a global specialist HIV company established in November 2009 by GlaxoSmithKline (LSE: GSK) and Pfizer (NYSE: PFE) dedicated to delivering advances in treatment and care for people living with HIV and for people who are at risk of acquiring HIV. Shionogi joined as a shareholder in October 2012. The company?s aim is to take a deeper and broader interest in HIV/AIDS than any company has done before and take a new approach to deliver effective and innovative medicines for HIV treatment and prevention, as well as support communities affected by HIV.

For more information on the company, its management, portfolio, pipeline and commitment, please visit?www.viivhealthcare.com.

About GSK GSK is a science-led global healthcare company with a special purpose: to help people do more, feel better, live longer. For further information please visit?www.gsk.com/en-gb/about-us.