Encyclopedia · immunomodulator
Ruxolitinib
The 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.
What it is
Oral ruxolitinib is approved for blood disorders such as myelofibrosis, and a cream is marketed for skin diseases. No form is approved for alopecia areata. Use for hair is off-label and prescription-only. Its deuterated descendant deuruxolitinib is the approved alopecia areata drug.
How it works
JAK1 and JAK2 blockade removes the interferon-gamma signature in the follicle. In the 2014 paper, systemic JAK inhibitors prevented alopecia areata in mice, topical ones reversed established disease, and three patients on oral ruxolitinib had near-complete regrowth within 5 months (Xing 2014).
What the studies show
- In an open-label pilot of 12 people on 20 mg twice daily for 3 to 6 months, 9 of 12 responded, with average regrowth of 92% at the end of treatment and no serious adverse events (Mackay-Wiggan 2016).
- A meta-analysis pooling tofacitinib and ruxolitinib found at least 50% improvement in 66% and relapse in most after stopping (Yu 2021).
- The 1.5% cream failed: in a phase 2 trial of 90 adults the open-label part looked promising, but the double-blind part showed no significant difference from vehicle, and the programme was stopped (Olsen 2020).
How it's used in studies
- Oral 20 mg twice daily for 3 to 6 months in the pilot (Mackay-Wiggan 2016); 1.5% cream twice daily in the cream trial (Olsen 2020).
Side effects and safety
- Oral: JAK-class risks (infection, low blood counts, cardiovascular events, clots); see baricitinib. The pilot reported no serious adverse events in 12 people.
- Cream: no significant safety issues in the alopecia areata trial.
Bottom line
Ruxolitinib is mostly of historical and mechanistic interest now that approved JAK inhibitors exist. The pill has only small uncontrolled evidence for hair, and the topical form has not worked for alopecia areata. Discuss with a doctor.
Studies 4
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 ↗Mackay-Wiggan J et al. Oral ruxolitinib induces hair regrowth in patients with moderate-to-severe alopecia areata. JCI Insight. 2016
Tested: oral ruxolitinib 20 mg twice daily, open-label
Result: 9 of 12 responded, with average regrowth of 92% at the end of treatment; no serious adverse events.
Read the study ↗Olsen EA et al. Ruxolitinib cream for the treatment of patients with alopecia areata. J Am Acad Dermatol. 2020
Tested: ruxolitinib 1.5% cream vs vehicle
Result: The open-label part looked promising, but the double-blind part showed no significant difference from vehicle.
Read the study ↗Yu DA et al. Treatment outcome of oral tofacitinib and ruxolitinib in patients with alopecia areata. Indian J Dermatol Venereol Leprol. 2021
Tested: oral tofacitinib or ruxolitinib
Result: At least 50% improvement in 66%; 74% relapsed within 3 months of stopping; infections and lab abnormalities were the commonest problems.
Read the study ↗Related
- DeuruxolitinibA 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.
- 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.
- TofacitinibThe first JAK inhibitor used off-label for alopecia areata; about a third to two thirds of patients regrow hair in open-label studies, but most relapse within months of stopping.
- 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.