Inhibrx Biosciences (INBX) Study Result summary

Chondrosarcoma trial results

• Ozekibart demonstrated a median progression-free survival (PFS) of 5.52 months versus 2.66 months for placebo, more than doubling PFS.

• Hazard ratio was 0.479, indicating a 52% reduction in risk of progression or death, with a p-value <0.0001.

• Disease control rate was 54% for ozekibart compared to 27.5% for placebo.

• Ozekibart was generally well tolerated; most adverse events were mild, with effective mitigation of hepatotoxicity risk.

• Key secondary endpoints included delay in pain and physical function deterioration, reinforcing clinical benefit.

Colorectal cancer and Ewing sarcoma expansion cohorts

• In late-line colorectal cancer, ozekibart plus FOLFIRI showed a 23% confirmed response rate and 92% disease control rate in heavily pretreated patients.

• In Ewing sarcoma, ozekibart plus irinotecan and temozolomide achieved a 64% response rate and 92% disease control rate.

• Most adverse events in both cohorts were mild and consistent with known profiles of combination agents.

• Early results in these difficult-to-treat populations are highly encouraging compared to standard therapies.

• Standard of care in late-line colorectal cancer yields only a 6% response rate.

Market opportunity and commercial outlook

• Chondrosarcoma prevalence in the U.S. is 2,000–3,000 patients, with no approved treatments; peak global revenue could exceed $500 million.

• Late-line colorectal cancer represents a $1.5 billion U.S. opportunity, potentially $3.5 billion if expanded to first-line RAS wild type.

• Ewing sarcoma has a similar market size to chondrosarcoma, with global peak revenue potential over $500 million.

• Combined, these indications represent a market potential greater than $2.5 billion, with further expansion possible in glioblastoma and other settings.