Pfizer and Arvinas are broadening their vepdegestrant programme to include more settings, as positive data is reported from the Phase Ib study of the drug to treat breast cancer.
Vepdegestrant is an orally administered protein degrader designed as a proteolysis targeting chimera (PROTAC) that targets both wild-type and mutant oestrogen receptor (ER) found in some breast cancers.
The collaboration between the two companies began in July 2021 in a $2.4bn deal to develop the PROTAC drug. Under the terms of the agreement, both firms would co-develop and market vepdegestrant.
In the abstract on data from a Phase Ib study (NCT04072952) presented at the ongoing 2023 San Antonio Breast Cancer Symposium (SABCS), the reported clinical benefit rate (CBR) was 37.1% with 200mg and 38.9% with 500mg of the drug amongst 71 patients who received either dose (abstract no. Abstract GS3-03). The treatment was generally well tolerated, with the most common side effects being fatigue and nausea. The CBR was higher in patients with ESR1 mutations, highlighting vepdegestrant’s clinical benefit in this breast cancer subtype.
The open-label study is evaluating vepdegestrant alone and in combination with Pfizer’s CDK 4/6 inhibitor Ibrance (palbociclib) in patients with oestrogen receptor positive/human epidermal growth factor receptor 2 negative (ER+/HER2-) locally advanced breast cancer, who have previously received hormonal therapy and chemotherapy in the locally advanced/metastatic setting.
A Phase III trial, dubbed VERITAC-3, studying vepdegestrant with Ibrance in patients who have not received prior CDK 4/6 inhibitor treatment, is currently recruiting patients. The companies have said they now plan to expand the development of vepdegestrant in earlier settings with CDK inhibitors pending additional data and if regulatory authorities get on board. One of those projects could be a Phase III trial of vepdegestrant with one of Pfizer’s investigational CDK4 inhibitors— PF-07220060.
According to GlobalData’s Pharma Intelligence Center, vepdegestrant is forecast to generate $1.35bn in sales in 2029.
GlobalData is the parent company of Pharmaceutical Technology.
In August of this year, the UK Innovative Licensing and Access Pathway Steering Group awarded vepdegestrant an Innovation Passport designation, which reduces the time it takes for a drug to get on the market and is aimed to streamline patient access to medicines. Both Pfizer and Arvinas will equally share development costs, commercialisation expenses, and profits.
