The Implantable, Subcutaneous, Tunable, Extended-release, Polymeric implant ISTEPTM) is our proprietary formulation that allows safe and effective extended-release drug delivery for six to twelve months. Our implants are optimized to be inserted subcutaneously in the office through a small incision. The proprietary iSTEP platform technology allows excellent API loading into a tunable release system which can be safely delivered to the subcutaneous space to deliver pharmaceutical agents that would otherwise have to be injected. The six-month duration of our drug delivery system makes it an excellent choice for pharmaceutical agents where compliance is a problem.
Patent numbers 9,452,083, 9,445,941, and 11,197,819.
The subcutaneous naltrexone implant, the iSTEP-N®, a 10 cc solid, bioabsorbable implant with a payload of 4.8 grams of naltrexone is Akyso's beachhead product. Our phase 1 clinical trial of the iSTEP-N® completed in April 2025 and the phase 1b 12-month PK study will commence in Q1 2026.
Release rate of any small molecule or large molecule API can be adjusted by adjusting the ratio of the control release polymers in the formulation. This allows for optimization of the pharmacokinetics for effective drug delivery. The implant is sturdy and can be manufactured in any size. It is stable at room temperature.
The non-reactive biocompatible material can be loaded with any medication. The two control release polymers have been used in FDA approved devices for decades and are well tolerated.
Our device is designed for easy subcutaneous implantation. The implant comes loaded with drug ready to use. It is Bioabsorbable and does NOT need to be removed. It can be implanted in an office procedure under local anesthesia.
Ultra-Long-Acting Naltrexone Implant Technology
The iSTEP-N® is an investigational, next-generation subcutaneous naltrexone implant designed to provide sustained opioid blockade with a single office-based procedure. This video demonstrates the mechanism of action and drug-release approach that aims to support long-term recovery by maintaining consistent therapeutic naltrexone levels for many months.
Our mission is to make treatment more accessible, improve adherence, and help patients stay engaged in recovery with less burden and more support.
iSTEP-N is an investigational product currently in development and is not approved or available for clinical use. This video is intended for educational purposes and to inform potential partners and investors about the technology platform. No claims are being made regarding safety or efficacy.
Our investigational iSTEP® implants are being evaluated in clinical studies. Programs and timelines are subject to change.
| Assets | Pre-Clinical | Phase 1a | Phase 1b | Phase 2 | Phase 3 |
|---|---|---|---|---|---|
| Opioid Use Disorder (OUD) | |||||
| iSTEP-N Naltrexone | |||||
| iSTEP-B Buprenorphine | |||||
| Alcohol Use Disorder (AUD) | |||||
| iSTEP-N Naltrexone | |||||
| Weight Loss / Metabolic Disease | |||||
| iSTEP-G GLP-1 Receptor Agonist | |||||
* iSTEP-N OUD: First-in-human Phase 1a completed; Phase 1b 12-month PK study commencing.
* iSTEP-B Phase 1a/1b/2 will be a seamless study design in subjects with OUD.
* All programs are investigational and have not been approved by the FDA.
NCT06216132 ·
NCT07064564
Akyso Therapeutics is a Biotech company which has been working in sustained release drug delivery since 2014. It's beachhead product currently under development is the Implantable Subcutaneous Tunable Extended-release Polymeric implant containing Naltrexone (iSTEP-N®). Our second product under development is the iSTEP-B, an extended release buprenorphine implant.
Addiction Medicine
The opioid crisis rose to prominence at a shocking rate. And the trail of destruction left in its wake has
damaged relationships, families, and communities. Recovery from opioid use disorder (OUD) is most successful when medications for OUD (MOUD) are combined with counseling and support. Compliance with currently available MOUD is poor. Akyso Therapeutics is working to deliver the first very
long acting treatment for OUD with a 6-12-month duration subcutaneous absorbable implant to address the vexing problem of compliance with MOUD.
In Q1 2026, Akyso therapeutics commenced formulation research and development working with a GLP-1 receptor agonist using our iSTEP technology with the aim of developing an iSTEP-G implant capable of deploying therapeutic levels of a GLP-1 receptor agonist following a single in office procedure.
This funding is to help with the cost of developing our subcutaneous, sustained-release naltrexone implant for opioid use disorder.
Financial conflict of interest disclosure is important to research integrity because it helps prevent research from being biased or influenced by personal or financial interests. Our policy regarding financial conflicts of interest is available here
.Our research and development team has developed the ISTEP technology; a safe and effective subcutaneous implant capable of significantly prolonging the effect of systemic pharmaceuticals.
Our proprietary formulation using control release polymers and naltrexone has been shown safe in 9-month GLP IND enabling toxicology studies, biocompatibility studies and a 3 month phase 1a human trial. .
In vitro and in vivo studies demonstrate excellent tunable release from our formulation. The iSTEP-N 10 cc implant demonstrated near-linear release of API over 12 months.
In Vivo studies in large and small animals have demonstrated excellent release kinetics from the implant with no evidence of toxicity. Phase 1a human trials showed excellent PK data with no serious adverse events and acceptable adverse events.
Our team has extensive experience in drug development.
Dr. Jeff Benner is an entrepreneurial physician and biotech innovator who transitioned from a distinguished 38-year career in retina surgery to focus full-time on addressing the opioid crisis. Since retiring from ophthalmology, he dedicated his career to addiction medicine and therapeutic innovation. He serves as Co-CEO of Akyso Therapeutics, where he leads the development of iSTEP-N™, a long-acting, bioabsorbable naltrexone implant designed to improve treatment outcomes in opioid use disorder (OUD).
Dr. Benner was Co-Principal Investigator on a multi-year, $15M NIH/NIDA grant that funded the development and early clinical testing of iSTEP-N™, which demonstrated safety, tolerability, and sustained therapeutic levels in first-in-human studies. His leadership helped secure FDA clearance of the company’s IND and progression of the program into Phase 1b trials.
In addition to his work at Akyso, Dr. Benner has founded multiple biotech startups, holds more than 10 issued U.S. patents, and has published extensively in both ophthalmology and addiction medicine. His entrepreneurial vision is grounded in a commitment to improving patient adherence and access to effective, long-acting therapies that can transform the trajectory of recovery for people with OUD.
Dr. Steven Cohen is a surgeon, inventor, and entrepreneur with over 30 years of clinical and research experience. He co-founded Akyso Therapeutics and serves as Co-CEO, where he directs strategy, regulatory development, and translational research for the company’s pipeline of long-acting, bioabsorbable drug-delivery implants for substance use disorders.
As Co-Principal Investigator on NIH-funded grants, Dr. Cohen has led the iSTEP-N™ implant program through preclinical development, FDA IND clearance, and successful first-in-human trials. He brings unique perspective as both a physician and an inventor, having served as investigator in more than 100 clinical trials and holding multiple patents, including innovations in drug delivery systems and surgical devices.
Dr. Cohen is also Clinical Professor of Ophthalmology at the University of South Florida, where he has trained generations of ophthalmologists. Earlier in his career, he co-developed a surgical device that was commercialized and is now marketed by Bausch + Lomb.
Dr. Pravin Soni brings more than 30 years of pharmaceutical development experience spanning formulation design, analytical validation, and CMC strategy. He has held senior leadership roles in both major pharmaceutical companies and emerging biotech ventures, where he successfully advanced multiple products from early development to commercial launch. At Akyso Therapeutics, Dr. Soni leads chemistry, manufacturing, and controls for the iSTEP-N™ implant, including polymer engineering, stability studies, and GMP process scale-up. His deep expertise in sustained-release systems and regulatory CMC filings ensures robust, reproducible manufacturing for both preclinical and clinical programs.
Dr. Josh Berman is a physician-scientist and clinical-regulatory strategist with more than 40 years of experience guiding drugs and biologics from concept through FDA approval. He served as Senior Vice President for Clinical Affairs at Fast-Track Drugs & Biologics, providing IND and NDA leadership for both small molecules and biologics, and previously directed the Office of Clinical and Regulatory Affairs at the NIH. Dr. Berman has authored more than 150 publications and was the clinical lead for several successful NDAs, including Miltefosine, Tafenoquine, and Artesunate. At Akyso Therapeutics, he directs regulatory strategy and clinical development planning, leveraging decades of FDA engagement and global infectious disease trial experience to accelerate approval pathways for the company’s iSTEP™ platform.
Chris Lumpkin is a medical device engineer with over 20 years of experience in surgical instrumentation, specializing in ophthalmology and neurosurgery. He has led the design and commercialization of numerous patented devices, including precision microinstruments and fiber-optic delivery systems. At Akyso Therapeutics, Mr. Lumpkin directs prototype and injector development for the iSTEP™ implant platform, combining his deep expertise in design, manufacturing, and quality systems to advance innovative, scalable drug-delivery technologies.
Adrienne O'Reilly is a quality assurance executive with over a decade of experience in global pharmaceutical development, including small and large molecules and combination products. At multiple organizations, she implemented the company's initial quality management system, scaling it throughout the product life cycle to late stage development, including NDA preparation. As the first QA employee at a multi-product company, she helped develop a combination product now sold commercially in the US, EU, and UK.
At Akyso Therapeutics, she combines her GMP QA and quality systems experience to oversee the implementation, operation, and scaled growth of the company's quality management system. Her product life cycle and compliance experience helps ensure product quality, patient safety, and data integrity throughout the development of Akyso products.
Dr. Mary Ellen Cosenza is a board-certified toxicologist and regulatory consultant with more than 25 years of global industry experience in nonclinical and regulatory strategy. She previously served as Executive Director of U.S. Regulatory Affairs and Toxicology at Amgen, where she supported successful INDs and BLAs across multiple therapeutic areas. At Akyso Therapeutics, Dr. Cosenza provides strategic guidance on preclinical safety, regulatory submissions, and FDA interactions for the iSTEP-N™ and iSTEP-B™ implant programs. She is a Diplomat of the American Board of Toxicology (DABT) and has authored over 100 peer-reviewed publications and book chapters in regulatory science.
Martha Riddle is a senior clinical development executive with more than 25 years of experience leading global clinical programs across psychiatry, neurology, and addiction medicine. She previously held executive positions at multiple biopharmaceutical companies, where she managed cross-functional teams responsible for clinical trial design, data analysis, and regulatory submissions. At Akyso Therapeutics, she advises on clinical strategy, protocol development, and data interpretation for Phase 1 and Phase 2 trials of the iSTEP platform. Her career reflects a commitment to advancing innovative, patient-focused therapies in neuropsychiatric and behavioral health disorders.
We are excited about this promising treatment for opioid use disorder!
Akyso Therapeutics
26627 Pemberton Drive
Salisbury, MD 21801