外用4%吡仑西平——一项新研究显示其能显著提高糖尿病神经病变患者的神经纤维密度——有望于今年在蒙大拿州用于PFS患者的临床试验。
2026年3月24日
亲爱的朋友们：
向西行吧，年轻人——具体而言，就是去蒙大拿州。因为在那里，或许能找到缓解由非那雄胺引发的持续性生殖器麻木症状的良方。
Way outside the Beltway
Yesterday, Stanley Kim, CEO of the San Diego-based biotech firm WinSanTor, announced a new strategy for getting his sole product, WST-057 (topical pirenzepine 4%), into the hands of perhiperal-neuropathy (PN) patients asap. That would be shifting away from the FDA’s Expanded Access Program (aka compassionate use) to The Treasure State’s Right to Try Program.
“While we previously explored traditional federal programs, we found they often carry ‘one-size-fits-all’ bottlenecks that aren’t ideal for a drug like ours. Because WST-057 is a topical treatment with established safety data, it’s the perfect candidate for a more modern, streamlined approach,” said Kim.
“Montana’s ‘Right to Try 2.0’ framework is much more suitable for our mission because it explicitly supports treatments for severely debilitating diseases like peripheral neuropathy, rather than just terminal ones. It allows for Experimental Treatment Centers that prioritize patient autonomy and medical freedom,” he added.
Montana Senate Bill 535, as it’s technically known, was signed into law on May 13, 2025. It’s widely regarded as the most deregulatory among all Right to Try statutes currently enacted in 41 US states. In contrast to the original model pioneered by Colorado in 2014, Montana’s law also allows biologics and cutting-edge therapies like gene-based treatments, while encouraging participation by manufacturers.
All Right to Try laws, however, allow patients to seek access only to experimental pharmaceutical products that have passed Phase 1 clinical trials, but are not yet FDA-approved. In the case of WST-057, the drug has already completed Phase 1 and Phase 2 trials, and is currently in the final development stages of Phase 3 trials.
Grow-Grow Decade on the horizon?
WST-057’s active ingredient, pirenzepine, an M1 selective muscarinic antagonist, was developed in the 1980s, and marketed throughout Europe and Asia in oral form to treat gastric ulcers. That, by reducing gastric acid secretion and muscle spasms.
Over the past 12 years, the WinSanTor team has demonstrated that pirenzepine rubbed directly onto the skin can regrow peripheral nerves damaged by diseases like diabetes, or by treatments like chemotherapy, which appears to be restoring feeling where numbness and pain had set in.
Such results have earned WST-057 a place in the hallowed halls of medical literature. Three months ago, a Canadian research team led by Vera Bril, MD, at Toronto General Hospital’s Ellen & Martin Prosserman Centre for Neuromuscular Diseases published a study titled Topical application of the antimuscarinic pirenzepine increased lower limb nerve fibre density in a phase 2a study in type 2 patients with diabetes with peripheral neuropathy in The Lancet’s EBioMedicine journal. It concluded that:
“[P]irenzepine administered once daily for 24 weeks in patients with [diabetic peripheral neuropathy] resulted in a significant increase in [intraepidermal nerve fiber density] at the ankle, a primary efficacy outcome measure. The effect of this intervention was seen over a relatively short period of time. This observation is encouraging and has implications for other proof-of-concept studies in patients with DPN.”
In addition to genital numbness, WST–057 could potentially relieve other PN symptoms that overlap with those reported by many PFS patients, including:
▪ Paresthesia (aka “pins and needles”): sharp, jabbing, throbbing or burning pain
▪ Extreme sensitivity to touch
▪ Intolerance to heat
▪ Excessive sweating, or inability to sweat
▪ Muscle weakness
Nuts & bolts of regaining sensation
WinSanTor recently began working with state officials to set up an operational framework that will allow eligible PN patients from anywhere in the world to travel to Montana seeking WST-057.
Although the program will be available to diabetic PN patients first, patients with other types of PN, including that resulting from finasteride use, can sign up immediately by completing this questionnaire.
Additionally, Kim provides the following checklist for those hoping to try the drug via participation in a clinical trial:
▪ Coordinate with Your Doctor: The treating physician must certify that you have a severely debilitating condition and have considered standard options. Share the EBioMedicine study with him or her. It provides the peer-reviewed evidence needed to support your request.
▪ Verify Your Eligibility: Under the Montana framework, patients must provide informed consent and acknowledge the experimental nature of the treatment. This is a program for those seeking to address the underlying disease or condition, not just manage pain.
▪ Prepare to Travel: Montana’s program requires your physical presence at a licensed Experimental Treatment Center. Start plotting out that trip now. Meanwhile, WinSanTor is working to bring similar programs to other regions, for those who might not be able to get to Montana.
▪ Consider the Cost: In addition funding your own travel, patients will have to buy a six-month supply of WST-057 for about $1,980 USD.
In terms of a timeline for running WST-057 clinical trials for PFS patients, Kim tells us that could happen as early as June.
“Our only hurdle now is raising a little more funding, which I’m working on as we speak,” he says.
Finasteride was originally developed by Merck & Co., Inc., and first approved by the US Food and Drug Administration in 1993 as Proscar (5 mg, for enlarged prostate), and again in 1997, as Propecia (1 mg, for hair loss).
In June 2021, Merck spun off its Organon subsidiary as an independent public company (NYSE: OGN). Founded in the Netherlands in 1923, Organon bills itself as a “global health care company dedicated to making a world of difference for women, their families and the communities they care for.”
Among the Merck products Organon acquired in the deal were Proscar and Propecia. To report adverse events for either finasteride product, call the Organon Service Center at (844)674-3200, or email Service_Center@Organon.com.
Anyone living in the US who suffers from PFS should also report his or her symptoms to the US FDA. Anyone living outside the US who suffers from PFS should report his or her symptoms to the US FDA as well as to his or her local DRA, as directed on our Report Your Side Effects page.
If you or a loved one are suffering from PFS, and feeling depressed or unstable, please don’t hesitate to contact the PFS Foundation as soon as possible via our Patient Support hotline: social@pfsfoundation.org
Thank you.