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, Turkey, December 2, 2025 (Newswire.com) - 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 18th 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 (Tmax) reached at 1.25(±0.54) and 1.50(±0.53) hours on day 1 and day 14, respectively.
Mean terminal elimination half-life (t1/2) 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 (Tmax) reached at 0.95(±0.16) and 1.00(±0.00) hours on day 1 and day 14, respectively.
Mean terminal elimination half-life (t1/2):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.
