Inhibrx BLA for Ozekibart Accepted by FDA in Chondrosarcoma

Inhibrx Biosciences secures FDA BLA acceptance for ozekibart in conventional chondrosarcoma, setting an April 14, 2027, PDUFA date and advancing oncology drug news for a disease with no approved systemic therapy.

FDA accepted Inhibrx's Ozekibart BLA on June 15, 2026, with a PDUFA goal date of April 14, 2027 under standard 10-month review; no filing issues identified.
The pivotal ChonDRAgon trial demonstrated a 52% reduction in progression risk vs. placebo (PFS 5.52 vs. 2.66 months) across 206 patients with unresectable or metastatic chondrosarcoma.
If approved, ozekibart would be the first FDA-approved systemic therapy for conventional chondrosarcoma; INBX shares rose 2.6% on the announcement.

Lead

Inhibrx Biosciences, Inc. (NASDAQ: INBX) announced on June 15, 2026, that the U.S. Food and Drug Administration has accepted for review its Biologics License Application for ozekibart (INBRX-109) in adult patients with unresectable or metastatic conventional chondrosarcoma, with a Prescription Drug User Fee Act goal date of April 14, 2027.

What Happened

The FDA's acceptance, which identified no filing issues, formally initiates a standard 10-month regulatory review. The BLA submission rests on data from the ChonDRAgon study, a randomized, placebo-controlled Phase 2 trial enrolling 206 patients across 67 global sites.

In ChonDRAgon, ozekibart delivered a statistically significant improvement in the primary endpoint of progression-free survival: 5.52 months versus 2.66 months on placebo, representing a 52% reduction in the risk of disease progression or death (hazard ratio 0.479; 95% CI 0.33–0.68; p<0.0001). The disease control rate reached 54% in the ozekibart arm versus 27.5% for placebo. The drug also demonstrated significant delays in deterioration of pain and physical function, key secondary endpoints for a condition where symptom burden is central to patient experience.

Drug Profile and Disease Context

Ozekibart is a tetravalent death receptor 5 (DR5) agonist antibody engineered to activate DR5, triggering apoptosis in tumor cells. Chondrosarcoma is the second most common primary bone malignancy and is historically resistant to cytotoxic chemotherapy and radiation. Surgical resection remains the only effective intervention for localized disease; patients with unresectable or metastatic disease have had no approved systemic treatment options.

Ozekibart carries Fast Track Designation (granted January 2021) and Orphan Drug Designation (granted November 2021), reflecting the unmet medical need in this rare tumor population. The safety profile from ChonDRAgon was broadly manageable, with fatigue, constipation, and nausea among the most common treatment-related adverse events; hepatotoxicity monitoring protocols were implemented given the mechanism of the DR5 agonist class.

Market Reaction

INBX shares gained 2.6% on the announcement. The FDA acceptance represents a critical value-inflection milestone for Inhibrx, which reported a net loss of $33.4 million and cash reserves of $161.7 million in the first quarter of 2026. A successful approval would represent the company's first commercial product.

Outlook

With no filing deficiencies flagged and a PDUFA date of April 14, 2027, Inhibrx Biosciences enters a 10-month standard FDA review period. A positive decision would establish ozekibart as the first approved systemic oncology drug news for conventional chondrosarcoma, addressing a patient population that has lacked systemic treatment options for decades. The company's Orphan Drug Designation also positions it for a seven-year period of U.S. marketing exclusivity upon approval. Near-term milestones include ongoing secondary endpoint readouts from ChonDRAgon, including overall survival data, and preparation of commercial infrastructure ahead of the April 2027 target.

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