What Vilobelimab's Failed Trial Actually Tells Us About InflaRx's Future

InflaRx (IFRX) pulled the plug on its Phase 3 study for Vilobelimab in May 2025 after disappointing interim results, but here’s the twist—the full data analysis revealed something the company thinks the market missed. When you dig into what happened, it raises interesting questions about clinical trial design, patient selection, and whether neutrophilic dermatoses treatment requires a different playbook.

Why The Trial Stumbled, But Maybe Shouldn’t Have

The trial targeting pyoderma gangrenosum enrolled 54 patients, with 30 completing the full six-month treatment window. The primary endpoint—complete target ulcer closure on two consecutive visits—missed statistical significance, which triggered the IDMC’s futility call. But here’s where it gets interesting: the secondary endpoints and post-hoc analyses told a different story.

Complete disease remission hit 20.8% in the Vilobelimab group versus just 5.6% on placebo. More impressively, 36.4% of treated patients saw their target ulcer volume shrink by more than 50%, compared to 16.7% in the control arm. These aren’t minor differences. Quality of life measures also shifted meaningfully—the Dermatology Life Quality Index dropped 31.1% for patients on Vilobelimab while actually ticking up slightly for placebo recipients.

Post-hoc statistical modeling using mixed model repeated measures analysis showed significant ulcer volume reductions from week 14 through week 26 favoring the treatment. Covariance analyses confirmed improvements in both ulcer volume and surface area. Translation: the drug appeared to work, but the study’s primary design may have been too rigid to capture it.

The C5aR Angle: Why Neutrophilic Dermatoses Matter

The scientific foundation here centers on targeting the C5a/C5aR pathway, which plays a key role in neutrophilic dermatoses—the class of inflammatory skin diseases that includes pyoderma gangrenosum. This pathophysiology makes sense: if you can suppress the neutrophil-driven inflammation cascade, you theoretically reduce ulcer formation and promote healing.

External experts haven’t written off the approach. While they acknowledge the primary endpoint miss, they view the dataset as supporting the broader rationale for this mechanism in this disease. The question now becomes whether Vilobelimab needed longer exposure or whether the endpoint itself needed rethinking for a patient population historically difficult to treat.

What’s Next: FDA Talks and Partner Hunting

InflaRx indicated it will engage with the FDA to explore alternative endpoints that might better reflect clinical benefit in pyoderma gangrenosum. The company also signaled that future development would likely require a partner—a practical reality given InflaRx’s current priorities. The oral C5aR inhibitor Izicopan (INF904) represents where management is focusing its chips.

The Financials Don’t Inspire Confidence

GOHIBIC—Vilobelimab’s approved formulation—generated €39,000 in U.S. revenue during the first half of 2025, slightly below the €42,000 from the same period a year prior. The drug maintains Emergency Use Authorization for COVID-19 in ventilated patients and EU authorization for SARS-CoV-2-induced acute respiratory distress syndrome, but commercial traction remains minimal.

IFRX has traded between $0.71 and $2.77 over the past twelve months. The stock is down 4.89% in premarket trading, reflecting investor skepticism about whether reanalyzed secondary endpoints can salvage a failed primary trial—and whether the company has the runway and resources to pursue rare disease indications without stronger commercial validation.