GEN Announces New Positive Phase 1 Trial Data of the Investigational Drug SUL-238 for Alzheimer's and Other Neurodegenerative Diseases

Phase 1 results show that SUL-238 is safe, well-tolerated, and demonstrates favorable pharmacokinetics with high CSF penetration in healthy elderly volunteers, supporting its advancement into further clinical development for Alzheimer's and other neurodegenerative diseases.

ANKARA, TR / ACCESS Newswire / December 2, 2025 / GEN Pharmaceuticals (GENIL.IS), Türkiye's leading specialty pharmaceutical company, has announced new positive results from its Phase 1 clinical trial evaluating the safety, tolerability, and pharmacokinetics (PK) of first-in-class, novel orally administered mitochondria-directed drug candidate SUL-238 in healthy elderly volunteers. The findings were presented at the 18^th Clinical Trials on Alzheimer's Disease (CTAD) in San Diego, CA (United States) today.

SUL-238 was originally discovered by Sulfateq and has since been further developed through a collaborative effort of Sulfateq and GEN as a novel therapeutic in neurodegenerative diseases.

This Phase 1 randomized, double-blind, placebo-controlled study evaluated the safety, tolerability, and pharmacokinetics (PK) after multiple-ascending doses (MAD) of orally administered SUL-238 in healthy elderly men and women (aged ≥40 years). The study included two cohorts with a treatment period of 14 days and a safety follow-up through 14 days after the last dose. 15 healthy adults in each cohort were randomized in a 2:1 ratio to receive SUL-238 or placebo. Total daily dose of SUL-238 was 4000 mg (2000 mg b.i.d., first cohort) or 4500 mg (1500 mg t.i.d., second cohort). SUL-238 demonstrated an excellent safety and tolerability profile after multiple doses in both cohorts, while demonstrating a favourable PK profile and a high cerebrospinal fluid (CSF) penetration, making it a promising candidate for further clinical development in neurodegenerative diseases, including Alzheimer's and Parkinson's diseases.

Key Findings:

Safety in both cohorts:

• No clinically significant changes were observed in physical and neurological exams, vital signs, ECG, and clinical laboratory parameters.

• AE rates were comparable between participants receiving SUL-238 and placebo.

• All AEs were of mild intensity or considered not related to SUL-238.

First cohort PK (2000 mg b.i.d.):

• SUL-238 was rapidly absorbed with a mean time to maximum plasma concentration (T_max) reached at 1.25(±0.54) and 1.50(±0.53) hours on day 1 and day 14, respectively.

• Mean terminal elimination half-life (t_1/2) was3.50(±1.06) hours on day 14.

• Mean trough plasma concentration of SUL-238 was 39.23(±24.31) ng/mL and 41.49(±18.20) ng/mL on day 8 and day 14, respectively.

Second cohort PK (1500 mg t.i.d.):

• SUL-238 was rapidly absorbed, with a mean time to maximum plasma concentration (T_max) reached at 0.95(±0.16) and 1.00(±0.00) hours on day 1 and day 14, respectively.

• Mean terminal elimination half-life (t_1/2):3.74(±1.84) hours on day 14.

• Mean trough plasma concentration of SUL-238 was 57.98(±31.08) and 60.63(±64.14) ng/mL on day 8 and day 14, respectively.

Abidin Gülmüş, Chairman of GEN, stated:
"We're greatly motivated by these new positive results of SUL-238 in our Phase 1 trial, which mark a key advance toward addressing Alzheimer's disease at its biological foundation."

Nadir Ulu, MD, PhD, Vice President of R&D at GEN, added:
"With its excellent safety and PK profile in this Multiple Ascending Dose Phase 1 trial, SUL-238 continues to represent a very strong drug candidate for further clinical development aimed at meeting the critical unmet needs in neurodegenerative diseases, including Alzheimer's disease.

About SUL-238
SUL-238 is a novel, first-in-class, hibernation-derived small molecule designed to target mitochondria, the 'powerhouse' of the cell. SUL-238 supports mitochondrial bioenergetics via complex I/IV activation and enhances mitochondrial function in various preclinical models for neurodegenerative, cardiovascular, and renal diseases, as well as in accelerated aging. SUL-238 exhibits the capability to cross the blood-brain barrier and has undergone extensive safety evaluation in preclinical and clinical Phase 1 studies. GEN licenses SUL-238 from Sulfateq B.V. for neurodegenerative disease applications.

About GEN:
Founded in 1998, GEN is Türkiye's leading specialty pharmaceutical company, focused on developing innovative therapies across multiple therapeutic areas. Through significant R&D investments and global collaborations, GEN is committed to advancing healthcare worldwide. The company develops and manufactures high-quality, competitive products at its GMP-certified production facility and continues its bold efforts in original drug development via two dedicated R&D centers.

About Sulfateq:

Sulfateq B.V. is an early-stage Dutch biotech company that fosters strategic collaborations with academic and industrial research centres to accelerate the development of innovative new medicines. It has developed a novel class of small molecules, the SUL-compounds, that maintain mitochondrial health.

For more information:
www.genilac.com.tr
www.sulfateqbv.com

Contact Information

Bulutay Güneş
Sr. Head of Corporate Brand
b.gunes@genilac.com

Fatih Gören
Investor Relations Manager
f.goren@genilac.com

SOURCE: GEN İlaç ve Sağlık Ürünleri A.Ş.

View the original press release on ACCESS Newswire