Encyclopedia · immunomodulator
Deuruxolitinib
A twice-daily JAK pill approved in the US in 2024 for adults with severe alopecia areata, giving about 3 in 10 people near-full scalp hair at 24 weeks.
What it is
Deuruxolitinib is an oral JAK1 and JAK2 inhibitor, a deuterium-modified version of ruxolitinib that lasts longer in the body. It was developed by Concert Pharmaceuticals and is now owned by Sun Pharma. It is approved for severe alopecia areata in adults only, not for pattern hair loss.
- US: approved in July 2024 at 8 mg twice daily, with a boxed warning for JAK-class risks. It is contraindicated in people who are poor metabolisers of the CYP2C9 enzyme and with moderate or strong CYP2C9 inhibitors.
- UK: NICE guidance published in July 2026 recommends it for adults with severe alopecia areata when supplied under the company's commercial arrangement, with CYP2C9 genotyping before starting. We could not confirm its marketing authorisation status.
- EU: we found no sign of an application to the European Medicines Agency.
How it works
It blocks JAK1 and JAK2, damping the interferon-gamma and related signals that drive the immune attack on follicles (Xing 2014). Because the body clears it through the CYP2C9 enzyme, genotype and interacting drugs matter.
What the studies show
- In the first phase 3 trial of adults aged 18 to 65 with at least 50% hair loss, at least 80% scalp hair at 24 weeks was reached by 29.6% on 8 mg, 41.5% on 12 mg and 0.8% on placebo. Sun funded it (King 2024).
- In the second phase 3 trial (517 people), the figures were 33.0% (8 mg), 38.3% (12 mg) and 0.8% (placebo) (Tsianakas 2026).
- Only 8 mg was approved in the US, even though 12 mg worked better in the trials.
- How long the response lasts after stopping was not assessed in the pivotal trials, which the authors list as a limitation (King 2024).
- No head-to-head trial against other JAK inhibitors exists.
How it's used in studies
- 8 mg or 12 mg twice daily, with or without food, for 24 weeks. The label dose is 8 mg twice daily.
Side effects and safety
- Most trial events were mild or moderate and in line with other oral JAK inhibitors (King 2024).
- The boxed warning covers serious infections, death, cancer, major cardiovascular events, clots and gastrointestinal perforation.
- Genetic and drug-interaction restrictions apply through CYP2C9.
Bottom line
Deuruxolitinib has two consistent industry-funded phase 3 trials for severe alopecia areata in adults. Its effect looks similar to baricitinib and ritlecitinib on indirect comparison, with extra need for genetic testing and twice-daily dosing. Long-term safety and relapse after stopping are not yet reported. It is a specialist's choice and not available in the EU as far as we found. Discuss with a doctor.
Studies 3
King B et al. Efficacy and safety of deuruxolitinib in adults with severe alopecia areata: THRIVE-AA1 phase 3 randomized, controlled trial. J Am Acad Dermatol. 2024
Tested: deuruxolitinib 8 mg or 12 mg twice daily vs placebo
Result: At least 80% scalp hair in 29.6% (8 mg), 41.5% (12 mg) and 0.8% (placebo); Sun-funded.
Read the study ↗Tsianakas A et al. Deuruxolitinib in severe alopecia areata: THRIVE-AA2 phase 3 trial. J Am Acad Dermatol. 2026
Tested: deuruxolitinib 8 mg or 12 mg twice daily vs placebo
Result: At least 80% scalp hair at week 24 in 33.0% (8 mg), 38.3% (12 mg) and 0.8% (placebo).
Read the study ↗Xing L et al. Alopecia areata is driven by cytotoxic T lymphocytes and is reversed by JAK inhibition. Nat Med. 2014
Tested: JAK inhibitors, including oral ruxolitinib
Result: Systemic JAK inhibitors prevented disease in mice, topical ones reversed it, and three patients on ruxolitinib regrew nearly all hair within 5 months.
Read the study ↗Related
- BaricitinibA once-daily pill that was the first drug approved for severe alopecia areata, regrowing hair in about a third of patients while they keep taking it.
- RitlecitinibA once-daily pill approved for severe alopecia areata from age 12, which regrows hair in about 1 in 4 people by 6 months and keeps improving for years.
- RuxolitinibThe JAK1/2 blocker whose first use in three alopecia areata patients in 2014 launched the JAK era for hair; the pill regrows hair in small studies while the cream failed.
- UpadacitinibA JAK1 pill already approved for other diseases that gave 45 to 55% of people with severe alopecia areata near-full scalp hair in two 2026 trials and is under regulatory review for hair.
- JAK inhibitors and hairJanus kinase (JAK) inhibitors are pills that regrow hair in severe alopecia areata, but they are not treatments for ordinary pattern thinning.
- Alopecia areataAn autoimmune condition where the immune system attacks growing hair follicles, causing round patches or total hair loss; three oral JAK inhibitors are approved for severe cases but hair usually goes again when treatment stops.