Forte Biosciences' FBRX shares surged 78.3% after the company reported positive top-line results from a phase Ib study evaluating its lead candidate, FB102, in patients with vitiligo. Treatment with FB102 demonstrated statistically significant improvements in facial depigmentation compared with placebo. The encouraging data also reinforced the candidate’s favorable safety profile, boosting investor optimism around its clinical potential in autoimmune diseases.
The phase Ib study enrolled 43 patients who were randomized in a 3:1 ratio to receive either FB102 or placebo. Participants received treatment for 12 weeks and were followed through week 24 to assess the durability of response. FB102 is an investigational anti-CD122 monoclonal antibody with a dual mechanism of action that could potentially provide broader immune pathway modulation than therapies targeting IL-15 alone while avoiding excessive suppression of regulatory T-cell function.
FBRX's Early-Stage Vitiligo Study Results in Detail
Forte Biosciences reported that in the protocol-defined efficacy-evaluable population of the phase I study, FB102 delivered a 29.6% mean improvement from baseline in the Facial Vitiligo Area Scoring Index (FVASI) at week 24 compared with a 7.9% improvement for placebo, translating into a placebo-adjusted benefit of 21.7% that reached statistical significance. Clinical activity emerged early, with statistically significant improvements observed by day 64, and treatment benefits continued through week 24 despite completion of the 12-week dosing period.
Year to date, FBRX shares have gained 34.6% compared with the industry’s 6.4% growth.
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The therapy showed even stronger efficacy in patients with more extensive disease involvement, defined by a baseline FVASI score of at least 0.75 (approximately one-quarter of facial depigmentation). In this subgroup, FB102 achieved a 43.2% mean improvement from baseline at week 24 compared with just 0.5% for placebo, resulting in a placebo-adjusted benefit of 42.7%. Among these patients, 58.8% achieved an FVASI50 response, indicating at least a 50% improvement in facial depigmentation, while 23.5% reached the more stringent FVASI75 threshold. By comparison, none of the placebo-treated patients in this subgroup achieved either response milestone.
Across the overall efficacy-evaluable population, 34.4% of FB102-treated patients achieved an FVASI50 response, and 12.5% achieved an FVASI75 response by week 24. Forte Biosciences also reported durable treatment responses, with patients continuing to improve after the 12-week treatment period had ended. FB102-treated patients recorded an additional eight percentage-point improvement in FVASI scores between weeks 12 and 24, while patients with greater baseline disease severity gained an additional 14 percentage points over the same period.
Overall, 84% of FB102-treated patients showed improvement from baseline through week 24, and none experienced disease worsening, compared with 27% of placebo recipients, who experienced disease worsening. Safety findings remained favorable, with only mild-to-moderate adverse events reported and a profile comparable to placebo.
Vitiligo is an autoimmune skin disorder in which NK and CD8+ T cells attack melanocytes, resulting in patchy skin depigmentation. According to Forte Biosciences, the disease affects an estimated two million people in the United States, while the global vitiligo treatment market is projected to expand to nearly $2.3-$2.7 billion by 2032-2034.
Beyond vitiligo, Forte Biosciences is also evaluating FB102 in an ongoing phase II study for celiac disease and in a separate early-stage study for alopecia areata, with top-line results from both expected later in 2026. These comprise Forte Biosciences' next major clinical catalysts.
Forte Biosciences, Inc. Price and Consensus
Forte Biosciences, Inc. price-consensus-chart | Forte Biosciences, Inc. Quote
FBRX’s Zacks Rank & Stocks to Consider
Forte Biosciences currently carries a Zacks Rank #3 (Hold).
Some better-ranked stocks in the biotech sector are Liquidia Corporation LQDA, Novavax NVAX and Amarin AMRN, each sporting a Zacks Rank #1 (Strong Buy) at present. You can see the complete list of today’s Zacks #1 Rank stocks here.
Over the past 60 days, estimates for Liquidia Corporation’s 2026 EPS have increased from $1.94 to $3.02. Over the same period, EPS estimates for 2027 have also increased from $3.79 to $4.92. LQDA shares have rallied 136.2% year to date.
Liquidia Corporation’searnings beat estimates in three of the trailing four quarters and missed in the remaining one, with the average surprise being 54.40%.
Over the past 60 days, estimates for Novavax’s 2026 loss per share have narrowed from 20 cents to 19 cents. Over the same period, loss estimates for 2027 have narrowed to 31 cents to 25 cents. NVAX shares have gained 39.9% year to date.
Novavax’s earnings beat estimates in each of the trailing four quarters, with the average surprise being 305.24%.
Over the past 60 days, estimates for Amarin’s 2026 loss per share have narrowed from $15.20 to 65 cents. Over the same period, loss per share estimates for 2027 have narrowed from $13.00 to 51 cents. AMRN shares have risen 8.4% year to date.
Amarin’s earnings beat estimates in three of the trailing four quarters, while missing the same on the remaining occasion, with the average surprise being 50.02%.
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