SION to Cut Workforce by Nearly Half After CF Study Failure, Stock Down
Shares of Sionna Therapeutics SION declined nearly 17% yesterday after the company announced a major organizational restructuring. As part of the restructuring, Sionna intends to reduce its workforce by about 46% to lower operating expenses and focus its resources on its prioritized cystic fibrosis (CF) programs.
The workforce reduction is part of a broader cost-cutting effort following setbacks in the company’s pipeline. Sionna expects the restructuring and related actions to cost approximately $6.4 million. Per Sionna, the measures are expected to extend its cash runway into the second half of 2029.
Year to date, SION’s stock has plunged 83.3% against the industry’s 7.8% growth.
Image Source: Zacks Investment Research
SION-719 Setback Led to a Shift in Priorities
The restructuring follows disappointing clinical results for SION-719, one of Sionna’s key pipeline programs. In the phase IIa PreciSION CF proof-of-concept study, Sionna evaluated SION-719, a nucleotide binding domain 1 stabilizer, as an add-on to Trikafta, Vertex Pharmaceuticals’ VRTX marketed CF treatment, in adults with CF who were homozygous for the F508del mutation.
The study did not meet its key endpoint as SION-719 failed to demonstrate a statistically significant reduction in sweat chloride levels, an important biomarker of CFTR function. Although SION-719 was generally well-tolerated, Sionna decided not to continue developing the candidate as an add-on treatment to Trikafta.
The company later conducted a post-hoc analysis and identified potential factors that may have affected the results, including pharmacokinetic outliers and complex interactions between SION-719 and Trikafta. After excluding three participants, the company reported a placebo-adjusted sweat chloride reduction of 8.6 mmol/L. However, this was a post-hoc analysis rather than the prespecified primary analysis, making the finding less conclusive.
SION’s Focus Shifts to Combo Treatment
Following the SION-719 setback, Sionna is concentrating its resources on its proprietary dual combination, SION-451 and SION-2222.
In a phase I study in healthy volunteers, SION-451 was evaluated in dual combination with either SION-2222 (galicaftor) or SION-109. The combinations met their safety, tolerability and pharmacokinetic objectives, including the targeted drug-exposure levels in CF participants.
Based on the overall phase I results, Sionna selected SION-451 + SION-2222 as its preferred combination for further development.
The company intends to advance this combination into the phase IIa AscenSION CF proof-of-concept study in the first quarter of 2027. This program is the key focus of Sionna’s CF development strategy.
SION’s Zacks Rank & Stock to Consider
Sionna currently carries a Zacks Rank #3 (Hold).
Some better-ranked stocks in the biotech sector are Precigen PGEN, currently sporting a Zacks Rank #1 (Strong Buy) and AC Immune ACIU, carrying a Zacks Rank #2 (Buy). You can see the complete list of today’s Zacks #1 Rank stocks here.
Over the past 60 days, estimates for Precigen’s 2026 bottom line have improved from a loss of two cents to earnings per share of 25 cents. Over the same period, earnings estimates for 2027 have risen from 25 cents to 86 cents. PGEN shares have gained 67.5% year to date.
Precigen’s earnings beat estimates in three of the trailing four quarters and missed in the remaining one, with the average surprise being 108.96%.
Over the past 60 days, estimates for AC Immune’s 2026 loss per share have narrowed from 84 cents to 60 cents. Over the same period, earnings estimates for 2027 remained unchanged at 17 cents. ACIU shares have lost 14.7% year to date.
AC Immune’s earnings beat estimates in each of the trailing four quarters, with the average surprise being 33.25%.
Zacks' Research Chief Names "Stock Most Likely to Double"
Our team of experts has just released the 5 stocks with the greatest probability of gaining +100% or more in the coming months. Of those 5, Director of Research Sheraz Mian highlights the one stock set to climb highest.
This innovative software-as-a-service firm upped its user base +22% year over year. That rate is increasing and margins are expanding as AI efficiencies take effect. Of course, all our elite picks aren't winners, but this one could far surpass earlier Zacks' Stocks Set to Double like D-Wave Quantum, which shot up +680.1%.
Free: See Our Top Stock And 4 Runners UpSionna Therapeutics, Inc. (SION) : Free Stock Analysis Report
Vertex Pharmaceuticals Incorporated (VRTX) : Free Stock Analysis Report
AC Immune (ACIU) : Free Stock Analysis Report
Precigen, Inc. (PGEN) : Free Stock Analysis Report
This article originally published on Zacks Investment Research (zacks.com).
