Gilead's Trodelvy and Keytruda Slow Triple-Negative Breast Cancer Progression

Analysts from Truist Securities have highlighted the potential market expansion for Trodelvy, an antibody-drug conjugate developed by Gilead, when used in combination with Merck's PD-1 inhibitor, Keytruda. This combination therapy has shown promising results in extending progression-free survival for patients with metastatic triple-negative breast cancer (mTNBC), an aggressive form of cancer. This development was shared in a recent update, suggesting that the combination could significantly increase Trodelvy's market presence in this field.

Currently, Trodelvy is approved as a standalone treatment for mTNBC, specifically for patients who have previously undergone at least two systemic treatments. The recent study called ASCENT-04/KEYNOTE-D19 involved over 440 patients with inoperable or mTNBC, all of whom had tumors expressing the PD-1 marker. The study compared the effectiveness of Trodelvy combined with Keytruda against the standard treatment of Keytruda and chemotherapy. The results, while not detailing specific data, indicated a significant improvement in progression-free survival with the Trodelvy-Keytruda combination.

Despite the positive progression-free survival results, data on overall survival rates, a crucial secondary measure of success, were not disclosed in this update. However, Gilead noted a favorable trend in overall survival, aligning with previously established safety profiles for both Trodelvy and Keytruda. Importantly, no new safety concerns were observed in the study.

Gilead plans to submit these results to regulatory bodies and intends to present comprehensive findings at an upcoming scientific conference. Analysts from Truist Securities anticipate that regulatory approval for this treatment regimen could be obtained by 2026. They also acknowledged potential future competition from other developing therapies, particularly PD-L1 combination treatments that integrate VEGF inhibitors.

Among potential competitors is Summit Therapeutics, in partnership with Akeso, which recently made headlines with its own Phase III trial results. Their bispecific antibody, ivonescimab, demonstrated a superior performance compared to Keytruda as a frontline treatment for non-small cell lung cancer (NSCLC). Ivonescimab targets both PD-1 and VEGF pathways, enhancing immune response and hindering the growth of blood vessels that support tumors. While the results were promising, analysts stress the necessity for further confirmation through more comprehensive survival data and diverse clinical trials.

Another player in this competitive landscape is BioNTech, which announced last month that its bispecific antibody, BNT327, yielded an objective response rate exceeding 85% in a Phase II study for NSCLC. This indicates BioNTech's active involvement in developing combination therapies targeting both PD-1 and VEGF pathways.

Overall, the combined use of Trodelvy and Keytruda represents a significant advancement in the treatment landscape for metastatic triple-negative breast cancer. If approved, it could offer a new frontline option for patients with this challenging diagnosis, potentially doubling the market reach for Trodelvy. However, this advancement comes with the anticipation of emerging competition from other combination therapies targeting similar pathways.