Quoin Pharma's Novel Rapamycin Delivery System Sparks Hope for Rare Vascular Malformations

By Charles Anderson

November 11, 2025 – Micro-cap pharmaceutical company Quoin Pharmaceuticals (NASDAQ: QNRX) is generating excitement in the rare disease space with recent announcements regarding its innovative approach to delivering rapamycin (sirolimus) topically. While rapamycin has shown promise in treating a variety of conditions, including certain cancers and autoimmune disorders, delivering it effectively to skin tissue has proven challenging. Quoin believes it has overcome these hurdles with its proprietary Invisicare technology, potentially unlocking a new treatment paradigm for conditions like microcystic lymphatic malformations (MLMs) and venous malformations (VMs).

Addressing an Unmet Need

MLMs and VMs are rare congenital conditions affecting an estimated 1 in 6,000 to 16,000 and 1-2 in 10,000 individuals, respectively. Currently, there are no FDA-approved treatments specifically for these conditions, leaving patients and families searching for effective therapies. “The lack of effective options is a significant burden for these patients,” says a physician specializing in rare vascular disorders. “Many live with chronic pain, disfigurement, and functional limitations.”

These malformations often involve abnormal lymphatic or venous vessels that can cause swelling, bleeding, and pain. Existing treatments are often palliative, focusing on symptom management rather than addressing the underlying cause.

The Challenge of Topical Rapamycin Delivery

Rapamycin works by inhibiting the mTOR pathway, a key regulator of cell growth and proliferation. This makes it a logical therapeutic target for conditions like MLMs and VMs, where dysregulation of the mTOR pathway contributes to the formation and growth of abnormal vessels. However, rapamycin presents a significant delivery challenge.

“Rapamycin is a lipophilic molecule with a high molecular weight,” explains a pharmaceutical formulation expert. “This makes it difficult for the drug to penetrate the skin barrier and reach the target tissues in sufficient concentrations.” Traditional topical formulations often struggle to deliver enough rapamycin to have a therapeutic effect, leading to disappointing clinical results.

Quoin's Invisicare Technology: A Potential Breakthrough?

Quoin Pharmaceuticals believes its Invisicare technology addresses these limitations. The company has not disclosed the specific details of the technology, but states it is designed to enhance drug penetration and delivery to the target tissues. In recent announcements, Quoin reported achieving target rapamycin loadings of 4% and 5% in its topical formulations.

“We’ve engineered a formulation that optimizes drug delivery at the target sites,” states Quoin’s CEO in a recent press release. “We believe this will lead to significantly improved efficacy and a better outcome for patients.”

Competition and Clinical Progress

Quoin is not the only company exploring topical rapamycin for vascular malformations. Palvella Therapeutics is currently conducting Phase 2 and Phase 3 clinical trials of its Qtorin rapamycin formulation for both VMs and MLMs. The company has received Fast Track and Breakthrough Therapy designations from the FDA for these indications.

“The competitive landscape is definitely heating up,” says an industry analyst. “Palvella has a head start in clinical development, but Quoin’s novel delivery system could give them a competitive edge.”

Quoin is currently focused on demonstrating the safety and efficacy of its topical rapamycin formulation in preclinical studies and plans to initiate clinical trials in the near future. Initial data from these studies is expected to be available in late 2026. The company recently completed a capital raise to fund these activities.

Investor Response and Market Outlook

The announcement of achieving target rapamycin loadings triggered a significant surge in Quoin’s stock price, rising over 66% in premarket trading. However, the stock remains volatile, reflecting the inherent risks associated with investing in micro-cap pharmaceutical companies.

“There’s a lot of excitement surrounding Quoin, but investors need to be cautious,” warns a financial advisor. “The company is still in the early stages of development, and there’s no guarantee that its clinical trials will be successful.”

Despite the risks, the potential market for topical rapamycin in vascular malformations is substantial. The rarity of these conditions means that even a small improvement in treatment outcomes could have a significant impact on patients’ lives. Furthermore, a successful topical rapamycin formulation could also be used to treat other skin conditions where mTOR pathway inhibition is beneficial, such as tuberous sclerosis complex and certain types of skin cancer.

Expert Commentary: A Cautiously Optimistic Outlook

Several experts in the field have expressed cautious optimism about Quoin’s approach. “The key will be demonstrating that the Invisicare technology can actually deliver a therapeutically relevant concentration of rapamycin to the target tissues,” says a dermatologist specializing in rare skin disorders. “If they can do that, it could be a game-changer for these patients.”

Another expert, a pharmaceutical formulation scientist, adds, “While the concept of enhancing topical drug delivery is not new, Quoin’s approach appears to be well-thought-out. The higher rapamycin loadings they’ve achieved are encouraging, but it will be crucial to see how that translates into improved efficacy and safety in clinical trials.”

As Quoin Pharmaceuticals moves forward with its clinical development program, investors and patients alike will be closely watching to see if its innovative delivery system can unlock the full potential of rapamycin for treating rare vascular malformations and other skin conditions. The ongoing competition from Palvella and other companies means that Quoin will need to demonstrate compelling clinical data to establish itself as a leader in this emerging field.