Viiv is a joint venture between rival pharma firms Pfizer and GlaxoSmithKline, which was launched last November. It aims to deliver advances in treatment and care for people living with HIV.
Hunt leaves Porter Novelli after five years. At Viiv, She will be responsible for handling all of the firm's external comms.
Viiv is focused on the research, development and commercialisation of HIV medications. It currently has ten medicines available including therapies such as Epzicom/Kivexa and Selzentry/Celsentri.
One of the company's aims is to 're-energise the pharmaceutical industry's participation in HIV by getting closer to those who live with the virus'.
Hunt has extensive experience working in the healthcare PR sector and previously worked at pharma firm Roche as PR manager for three-and-a-half years.
Prior to that, she worked at Porter Novelli's sister Omnicom agency Ketchum as senior account executive.
Porter Novelli is now looking to recruit a replacement for Hunt.
The UK healthcare practice is being headed in the interim by EMEA head of healthcare Shipra Singh, who joined the agency from Hill & Knowlton in March.
Singh joined from her role as head of strategic services at H&K, where she develeoped new offerings for the agency in emerging areas including clinical trial recruitment and retention.