Harpoon's TriTAC Programs Show Reduction in Tumor Size, Stable Disease Across Solid Tumors

Harpoon Therapeutics Inc HARP provides updated interim data from the ongoing dose-escalation portion of the Phase 1/2a trial for HPN424 in patients with metastatic castration-resistant prostate cancer (mCRPC).
Data were presented at the American Society of Clinical Oncology Virtual Annual Meeting.
15/74 (20%) patients had a prostate-specific antigen (PSA) decreases from baseline ranging from -2% to -76%, including four patients with PSA50 response and two patients with PSA30 response
Treatment duration of fewer than 24 weeks was observed in 15 of 74 (20%) patients, including 8 of 17 (47%) chemo-naïve patients.
Reduction in circulating tumor cells was seen in 36 of 64 (56%) patients with available baseline, and on-treatment CTC counts.
Cytokine release syndrome (CRS) has been transient and manageable, with 4% of patients experiencing severe CRS.
Also, three TriTAC clinical programs (HPN424, HPN536, and HPN328) have shown tumor size reductions or stable disease and meaningful treatment duration.
Price Action: HARP shares are down 0.63% at $15.76 during the market session on the last check Monday.