Phase II study of magrolimab combined with docetaxel in previously treated metastatic advanced solid tumors

Background: Novel treatments are needed to improve the poor prognosis of metastatic cancers. The ELEVATE Lung&UC study evaluated magrolimab plus docetaxel in patients with metastatic non-small cell lung cancer (mNSCLC), metastatic small cell lung cancer (mSCLC), and metastatic urothelial carcinoma (mUC). Methods: This phase II, open-label, multi-arm study enrolled patients who had received 1-2 (mNSCLC, mSCLC) or 2-3 prior lines of therapy (mUC) in the locally advanced/metastatic setting. A safety run-in (SRI) cohort (mNSCLC/mSCLC/mUC) followed by a phase II cohort (three groups: mNSCLC, mSCLC, mUC) were planned. Primary endpoints were incidence of treatment-emergent adverse events (TEAEs; SRI and phase II) and objective response rate (ORR; phase II). Results: The SRI cohort (n = 9) had no dose-limiting toxicities. In phase II (mNSCLC, 29 patients; mSCLC, 42 patients; mUC, 26 patients), ORRs were 17.2% (mNSCLC), 4.8% (mSCLC), and 3.8% (mUC). Grade ≥3 magrolimab-related TEAE rates were 48.3% (mNSCLC), 47.6% (mSCLC), and 57.7% (mUC). A fatal TEAE suspected as magrolimab related (intracranial hemorrhage) occurred in one patient with mSCLC and brain metastasis (phase II). The study was closed early, which limited the interpretation of results due to short follow-up and limited endpoint maturity. Discussion: Adding magrolimab to docetaxel had manageable toxicity but no meaningful improvement in efficacy. These results provide insight into the safety and efficacy of anti-CD47-containing therapies and reinforce the need for treatments that address the unmet needs of patients with previously treated metastatic solid tumors.