Gilead Sciences to buy 49.9% stake in Pionyr Immunotherapeutics for $275m

The deal also provides Gilead with an exclusive option to acquire the remaining stake in Pionyr for around $315m. The shareholders of Pionyr will secure up to an additional $1.15bn in future milestone payments based on the achievement of certain development and regulatory milestones.

Gilead Sciences chairman and CEO Daniel O’Day said: “The agreement represents important progress as we continue to build out Gilead’s presence in immuno-oncology with innovative and complementary approaches.”

Pionyr Immunotherapeutics is engaged in the development of first-in-class cancer immunotherapies.

The company has designed Myeloid Tuning, a research approach that will help rebalance the tumour microenvironment (TME) to boost anti-tumour immunity.

Myeloid Tuning therapies are believed to treat patients who currently do not benefit from checkpoint inhibitor therapies.

Pionyr has designed PY314 and PY159 programmes to selectively diminish and reprogramme certain tumour-associated macrophages responsible for immunosuppression.

PY314 is designed to target TREM2 protein that is commonly observed on the surface of a certain type of immunosuppressive and pro-tumour myeloid cells, while PY159 is designed to target TREM1 protein that is expressed on multiple immunosuppressive myeloid cells such as macrophages, neutrophils and myeloid-derived suppressor cells.

The company intends to submit investigational new drug (IND) applications with the US Food and Drug Administration for both PY314 and PY159 in the third quarter of this year.

As per terms of the deal, Gilead can exercise its exclusive option upon completion of phase 1b studies for PY314 and PY159 or earlier by paying $315m option exercise fee.

Pionyr will also secure additional funding for the PY314 and PY159 clinical programmes, as well as ongoing research and development programmes.

Pionyr president and CEO Steven James said: “This agreement underscores the value of our myeloid tuning platform and the potential of our pipeline of antibody therapeutics designed to turbocharge the immune system within the tumour microenvironment.”

Subject to customary closing conditions, the deal is expected to be completed within a short time. BofA Securities is serving as financial advisor to Gilead, while Centerview Partners is acting as financial advisor to Pionyr.

In May this year, Gilead signed a 10-year collaboration deal worth up to $1.97bn with Arcus Biosciences to co-develop and co-commercialise the current and future cancer therapeutic product candidates in the latter’s pipeline.