Steminent Biotherapeutics Inc Receives FDA Approval to Test Fat-Based Stem Cell Product to Treat Spinocerebellar Ataxia

Steminent Biotherapeutics Inc. is a biotechnology company based in Taipei, Taiwan, with subsidiary offices in San Diego and Shanghai. It is developing stem cell-based treatments for neurological conditions for which there are presently no treatment options.

The main product developed by Steminent is “Stemchymal.” Stemchymal consists of fat-based stem cells isolated from healthy donors. The cells are isolated from the fat (collected by means of liposuction), isolated, & standardized according to Good Manufacturing Practices that allows them to be administered to human patients. These fat-based mesenchymal stem cells contain a cornucopia of growth factors, cytokines, and other molecules that promote healing. They are also safe. Steminent scientists have shown that Stemchymal cells can be grown in culture for extended periods of time without becoming genetically altered. Stemchymal cells also neither form tumors in laboratory animals, nor elicit inflammatory reactions. Therefore, tissue matching is not required before administering them. Finally, Phase I clinical trials in human patients established the safety of Stemchymal when administered to people.

In Taiwan, Stemchymal has been approved for three different clinical trials. At the Taipei Veterans General Hospital, physicians are testing Stemchymal to treat osteoarthritis of the knee, spinocerebellar ataxia (a neurodegenerative condition), and vascular conditions. A recently approved application also allows testing Stemchymal to treat patients with diabetes mellitus.

In the United States, the Food and Drug Administration has “raised no objections” Steminent’s Investigational New Drug (“IND”) application that proposes to test Stemchymal as a treatment for polyglutamine spinocerebellar ataxia (“PolyQ SCA”).

Spinocerebellar Ataxias refer to a cluster of devastating, inherited neurodegenerative diseases that are relatively rare (between 2-7 per 100,000). These diseases are characterized by degeneration of the cerebellum, a part of the brain that regulates movement, and, sometimes, the spinal cord. Spinocerebellar ataxias (SCAs) are classified according to the altered genes that cause the disease. The symptoms of SCAs tend to include an uncoordinated gait, poor hand-eye coordination, and abnormal speech (dysarthria). There are no treatments for SCAs, and supportive measures are usually used.

Some SCAs are caused by the expansion of a portion of genes that encode stretches of the amino acid glutamine. Glutamine stretches seem to act as a flexible region that allows different portions of the protein to interact with each other.  When these glutamine stretches expand, the protein does not fold properly and aggregates, forming insoluble, toxic globules in the cell that cause cell death. Other mechanisms may be at work as well, such as mRNA toxicity, loss of protein function, or some other, as yet, uncharacterized mechanisms. There are more than 30 subtypes of SCA, and the following types of SCAs include poly-glutamine expansions: SCA1, SCA2, SCA3, SCA6, SCA7 and SCA17. The amino acid glutamine is encoded by the codons “CAG” and “CAA” stretches of these codons can cause DNA polymerase to slip, which causes the insertion of extra codons and expansion of the polyglutamine stretches.

The age of onset associated with PolyQ SCA disease patients can range from 20-50 years old. Not only are SCAs life-threatening diseases, but the extended physical handicaps imposed on the patient place a heavy burden on the patient’s family and healthcare providers.

As stated, there are no cures for SCAs, but Steminent has conducted a Phase I/II trial with SCA patients and showed that Stemchymal is safe for SCA patients. There were “no biological-related adverse effects observed in the 12-month follow-up. Additionally, patients seemed to improve while on Stemchymal. These functional improvements were maintained for up to 6 months.

In December 2015, the FDA designated Stemchymal as an Orphan Drug for the treatment of PolyQ SCAs. The Orphan Drug Designation grants “orphan status” to treatments of rare indications that affect fewer than 200,000 people in the U.S. This Orphan Drug Designation allows Steminent a seven-year window during they will enjoy “market exclusivity upon approval of Stemchymal^® and other development incentives including tax credits for clinical research costs and Prescription Drug User Fee Act (PDUFA) fee exemption.”

Managing Director of Steminent USA, Dr. Jennifer Ho, said, “Our Phase II Stemchymal® SCA program includes double blinded, randomized, and placebo-controlled trials to evaluate Stemchymal® SCA for safety and evidence of efficacy for treating PolyQ SCA in three countries. The first of these Phase II trials is currently enrolling patients in Taipei, and now with FDA consent, we are very pleased to initiate this US orphan designated drug trial. ReproCELL, our Japan partner, has also submitted its CTN to the PMDA to assess Stemchymal® SCA in treating PolyQ SCA in Japan.”

Dr. Susan Perlman, Clinical Director, UCLA Ataxia Center, Professor of Neurology, UCLA, and Medical Director; National Ataxia Foundation, said of Steminent’s clincal trial, “as there are currently no approved treatments for this progressive, irreversible disease, we are encouraged by the possibility that Stemchymal® cell therapy may demonstrate safety and therapeutic benefit in these patients.” According to Dr. Perlman, “It is estimated that about 15,000 people in the USA suffer from PolyQ SCA disease.”

With FDA approval in hand, Steminent will prepare the US trial sites and commence patient enrollment.