Compassionate Use Program for WinSanTor’s Peripheral Neuropathy Treatment Now in Place

GoFundMe campaign set up to expedite topical pirenzepine 4% prescriptions for PFS patient

Feb. 3, 2025

Dear Friends:

While it may be several years before the US Food and Drug Administration approves topical pirenzepine 4% (WST–057) as a treatment for the types of peripheral neuropathy (PN) afflicting scores of PFS patients, WinSanTor is scrambling to get its drug into their hands long before that.

The San Diego-based biotech firm has created an Expanded Access Program (commonly known as compassionate use) for WST–057, meaning patients in the US who suffer from the condition can ask their doctors to file an FDA application requesting a prescription. If approved, the Rx is forwarded to WinSanTor for filling.

The move comes four months after WinSanTor launched a survey seeking input from PFS and PSSD patients who suffer from what are medically known as sexual-sensory disorders (SSDs), genital numbness most prominent among them.

Capital crunch

“Thanks in part to that survey, we now have nearly 10,000 subscribers to our newsletter,” says WinSanTor CEO Stanley Kim. “But to date, just a few hundred PN sufferers have signed up for our compassionate use program.”

The latter shortfall presents a short-term challenge for WinSanTor.

“To bring WST–057 to market here in the US, and make it available to everyone afflicted by PN, we need to complete phase three of our clinical trials. That will involve more than 700 patients worldwide, and cost over $100 million dollars,” Kim tells us. 

“The good news is, the European Medicines Agency (EMA) has provided us guidance for approval in Europe, and we’re close to securing phase-three funding for Europe. The frustrating part is that virtually none of it can be spared for compassionate use in the US—which costs about $300 per patient per month over a course of six months.”

Never dissuaded from his mission, however, Kim has launched a GoFundMe campaign with a target goal of $200,000. If successful, the effort, which has already yielded $31,000, will significantly reduce the cost of treatment for each patient, making it more accessible to those in need.

Kim notes that diabetic PN patients participating in the clinical trials will have dibs on the initial production of WST–057. “That said, we’ll be seeking to expand into other indications as soon as possible—including PFS.”

Old dog, new fix

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 decade, 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.

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

If you’ve already signed up for the WST–057 Compassionate Use Program, no need to do it again. If not, please do so here. For an exclusive look at WST–057 in use, click here.

To help support WinSanTor’s GoFundMe campaign to reduce the cost of WST–057 for patients approved for compassionate use of the drug, click the image below.

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.