Subcutaneous Anifrolumab Represents a New Frontier in SLE Management

The phase 3 TULIP-SC trial showed that 56.2% of patients treated with subcutaneous anifrolumab achieved meaningful disease control at week 52 versus 37.1% with placebo—a statistically significant and clinically relevant difference that met the prespecified week-52 primary endpoint.

The week-52 durability and magnitude of response align with prior intravenous anifrolumab data while offering an alternative route of administration. A subcutaneous, self-administered formulation can increase patient autonomy and lessen infusion-clinic workload, extending established anifrolumab benefit into a more practical setting.

At week 52, 56.2% of treated patients were BICLA responders versus 37.1% with placebo (treatment difference 19.1%; 95% CI, 9.0–29.2; P = .0002), with the primary endpoint defined as meaningful disease control by BICLA response. Secondary findings included steroid-sparing advantages—maintenance of low or reduced oral corticosteroid doses from week 40 to week 52 occurred in 56.2% versus 34.0% (treatment difference 22.3%; 95% CI, 12.3–32.2; P < .0001)—and an earlier time to disease-activity response (41.5% vs 22.6%; HR 2.2; P < .0001). The subcutaneous anifrolumab arm showed consistent secondary improvements at prespecified assessment windows, supporting the primary disease-control outcome and clinically meaningful secondary effects at week 52.

Safety analyses indicated overall tolerability with adverse-event rates comparable to intravenous administration and no new safety signals in the study population. Routine immunologic and infection vigilance remains appropriate given the mechanism of action; the safety dataset did not reveal unexpected patterns that would require immediate additional precautions. In sum, tolerability was acceptable and consistent with prior anifrolumab experience.