Inhibrx (NASDAQ: INBX) loss widens while R&D falls and interest costs jump

What happened

Inhibrx Biosciences, Inc. (NASDAQ: INBX) reported a third-quarter net loss of $38.7 million, up from $35.3 million a year earlier.

The loss was $2.46 per share, against $2.28 in the third quarter of 2025. It widened even though research spending fell, because the cost of carrying debt rose sharply.

Cash was $199.5 million on Sept. 30, up from $124.2 million at Dec. 31, 2025. Over the same stretch, net long-term debt rose to $276.7 million from $100.6 million. Stockholders' equity of $8.0 million turned into a deficit of $85.9 million.

Key numbers

Metric	Latest	Change	Source
Net loss, Q3	$38.7 million	from $35.3 million	SEC 8-K Exhibit 99.1
Loss per share, basic and diluted	$2.46	from $2.28, +$0.18	Calculated from SEC 8-K
Total other expense, Q3	$7.0 million	from $1.4 million, +$5.6 million	Calculated from SEC 8-K
Research and development expense, Q3	$26.0 million	from $28.5 million, -$2.5 million	Calculated from SEC 8-K
General and administrative expense, Q3	$7.8 million	from $5.3 million, +$2.5 million	Calculated from SEC 8-K
Cash and cash equivalents, Sept. 30, 2026	$199.5 million		SEC 8-K Exhibit 99.1

Read more: Inhibrx Biosciences (INBX) company research

Where the loss came from

Total other expense was $7.0 million, compared with $1.4 million in the third quarter of 2025. Inhibrx says the increase is mainly higher interest expense on a $275.0 million loan balance, against $100.0 million a year earlier.

Operating costs moved in opposite directions. Research and development expense fell to $26.0 million from $28.5 million. Inhibrx ties the drop to lower clinical trial costs, because enrollment finished in its ozekibart trial in conventional chondrosarcoma, and to reduced headcount.

Higher contract manufacturing expense offset part of that decline. Inhibrx says the work supports its Biologics License Application for ozekibart in conventional chondrosarcoma.

General and administrative expense rose to $7.8 million from $5.3 million. Inhibrx says the increase is mainly pre-commercialization spending on market access, launch and communication materials as it prepares for a possible launch of ozekibart in conventional chondrosarcoma.

The quarter also carried $2.0 million of revenue. It was an upfront payment received in September 2026 from Pfizer, Inc. for a non-exclusive license of certain patent rights. Inhibrx recognized no revenue in the third quarter of 2025. Loss from operations narrowed to $31.7 million from $33.8 million.

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Why it matters

The operating picture improved while the financing picture worsened. By OptimistFi's calculation, other expense rose $5.6 million year over year, more than the increase in net loss. The narrower operating loss absorbed part of the higher interest cost. Financing now makes up a bigger share of the loss than it did a year ago.

The nine-month view is flatter. Net loss was $108.8 million for the first nine months of 2026, compared with $107.2 million a year earlier.

OptimistFi has argued that INBX works only if its platform produces differentiated clinical evidence before cash burn and balance-sheet pressure force unattractive dilution. This quarter leaves that test open. Debt and the equity deficit grew, yet cash is higher than at the end of 2025.

The same release offers a counterweight. Cash, lower research spending and continuing clinical milestones mean the wider loss does not by itself show immediate financing stress or forced dilution.

What's next

The nearest dated event is the annual Connective Tissue Oncology Society meeting in Seoul, South Korea, on Nov. 19-20, 2026. Inhibrx plans to present updated Phase 1/2 results for ozekibart combined with irinotecan and temozolomide in refractory Ewing sarcoma.

Two readouts are expected around mid-2027. One is the initial result of the Phase 2 expansion of the HexAgon study of ordastobart with pembrolizumab in head and neck squamous cell carcinoma. That expansion is expected to add about 50 HPV-positive oropharyngeal patients. The other is initial Phase 1/2 results for ordastobart in perioperative non-small cell lung cancer.

Inhibrx says commercial readiness for ozekibart in chondrosarcoma is advancing in line with the regulatory review timeline. Clear activity in the coming data would support the platform argument. Weak data would leave the loan and the equity deficit carrying more of the story.

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