Merck & Co (MSD) has reported that its Phase III KEYNOTE-522 clinical trial of Keytruda to treat high-risk, early-stage, triple-negative breast cancer (TNBC) met its overall survival (OS) endpoint.

Keytruda is an anti-PD-1 therapy and was assessed in combination with chemotherapy as a pre-operative (neoadjuvant) treatment and then as a monotherapy post-surgery (adjuvant).

The double-blind randomised study involved a total of 1,174 patients.

Participants were assigned in a 2:1 ratio to receive either Keytruda with chemotherapy or a chemotherapy-placebo regimen.

The treatment regimen comprised Keytruda plus chemotherapy with paclitaxel and carboplatin, followed by Keytruda plus chemotherapy with cyclophosphamide and either doxorubicin or epirubicin as neoadjuvant therapy before a surgical procedure, followed by Keytruda monotherapy as adjuvant therapy post-surgery.

Pathological complete response (pCR) rate and event-free survival were the trial’s primary endpoints while OS was the key secondary endpoint.

How well do you really know your competitors?

Access the most comprehensive Company Profiles on the market, powered by GlobalData. Save hours of research. Gain competitive edge.

Company Profile – free sample

Thank you!

Your download email will arrive shortly

Not ready to buy yet? Download a free sample

We are confident about the unique quality of our Company Profiles. However, we want you to make the most beneficial decision for your business, so we offer a free sample that you can download by submitting the below form

By GlobalData
Visit our Privacy Policy for more information about our services, how we may use, process and share your personal data, including information of your rights in respect of your personal data and how you can unsubscribe from future marketing communications. Our services are intended for corporate subscribers and you warrant that the email address submitted is your corporate email address.

An independent Data Monitoring Committee conducted an interim analysis that revealed a statistically significant and clinically meaningful improvement in OS for patients who received the Keytruda regimen versus pre-operative chemotherapy.

Keytruda’s safety profile aligned with previous studies, showing no new safety concerns.

In the US, Keytruda is already approved for two indications related to TNBC.

It is intended for use with chemotherapy as a neoadjuvant treatment and as an adjuvant treatment post-surgery for patients with high-risk early-stage TNBC.

It is also approved in combination with chemotherapy for patients with locally recurrent, unresectable, or metastatic TNBC expressing PD-L1.

Merck Research Laboratories global clinical development vice-president Dr Gursel Aktan said: “This is a significant milestone, as it is the first time an immunotherapy-based regimen has demonstrated a statistically significant overall survival benefit compared to chemotherapy alone in patients with high-risk early-stage triple-negative breast cancer.

“To have achieved overall survival from this landmark study is highly encouraging and builds upon the positive pathological complete response and event-free survival results that led to approvals for this regimen around the world.”

Earlier this month, MSD discontinued a Phase III trial investigating a co-formulation of vibostolimab and pembrolizumab (Keytruda) for patients with resected high-risk melanoma (Stage IIB-IV).