Trehalose
- Márcio
- Oct 26, 2023
- 3 min read
According to Karen Hohe Suchomel's testimony in the "4-AP" support group on October 24, 2023, Seelos Therapeutics stopped the Trehalose clinical trial at week 36, a little over halfway through the planned 52-week trial. The study began in June 2022 and was scheduled to end in June 2024. Karen had been participating from the beginning, as had other American patients. The reason? The money had run out.
It's incredible that Seelos failed to adequately plan and fund the costs of a clinical trial registered and under review by the FDA. This mid-treatment interruption due to "lack of funds" is extremely frustrating for the patients who were participating in the study, as well as for all ataxia patients awaiting the results, as well as caregivers, researchers, physicians, and other stakeholders.
The initial plan was to recruit up to 245 patients with SCA3 ataxia from various sites within and outside the United States. Three clinical trial sites were planned to open in Brazil, including one at UNICAMP, but the study was paused before Brazilian patient recruitment began. The same occurred in Portugal and other sites outside the United States, where the STRIDES study was already underway.
According to Karen, the clinical trial was supposed to last a year, with weekly intravenous infusions of the drug (90.5 mg/mL) into patients. The infusions were performed in the patients' homes—a nurse would visit and perform the procedure, which lasted about an hour. The American patient posted in a Facebook support group that she received 36 infusions, but that Seelos discontinued the study at week 36, citing "financial issues."
The trehalose molecule (a type of sugar) has (potentially—this is what the clinical trial would prove) the ability to break down toxic aggregates of malformed proteins (due to a mutation in the gene that synthesizes such proteins). These protein aggregates affect various cellular functions and can cause neuron death (neuronal loss) in the cerebellum and other areas of the nervous system. It is because of this neuronal loss (which can be identified on MRI scans as cerebellar atrophy) that the symptoms of ataxias arise.
When asked how she felt after receiving 36 Trehalose infusions, the patient reported that, because of the way it works (reducing toxic protein aggregates), Trehalose does not "cure" ataxia, but it can potentially slow the progression of the disease by helping the body eliminate malformed proteins through natural mechanisms. Therefore, she did not expect to feel "better" (in the sense of a cure or a reduction in existing symptoms), but she did expect "her ataxia to progress more slowly." This effect is difficult for the patient to quantify, but can be objectively measured using specialized scales that measure the progression of ataxia symptoms, such as the SARA scale, relative to the "normal" rate of progression measured in natural history studies for the same ataxia, in this case, spinocerebellar ataxia type 3 (SCA3).
Karen reported that from what she could feel, her neuropathy (a symptom of ataxia) continued to progress slowly over the 36 weeks she took the medication, but that the progression of her ataxia as measured by the SARA scale was quite stable.
In other words, with Trehalose infusions, “the ataxia did not regress or stop progressing, BUT it began to progress more slowly,” which is already a great advance for patients, both for the better quality of life and for giving them more time to wait for FDA approval of other therapies that can effectively halt the course of the disease (for example, ASO gene therapies).
Karen also reported that each weekly infusion took an hour, and that she "still has packets of the medication stocked at home," as she received enough for the entire year and only used it for 36 weeks. In other words, the nurse administering the injections simply stopped coming after week 36, as Seelos could no longer afford the cost of administering the medication weekly in the patient's home. However, the study continued normally for patients with ALS (Amyotrophic Lateral Sclerosis), for whom Trehalose is also being tested. The study was stopped only for the recruited patients with ataxia.
According to Dr. Susan Perlman, Trehalose remains a promising molecule for delaying the progression of SCA3 and it is possible that the Seelos Therapeutics study for patients with SCA3 ataxia will be resumed later this year (the study was not canceled, it was just interrupted (paused) due to alleged financial difficulties).
The Trehalose study is SLS-005 in NAF's pipeline for SCA3. See
Registration on clinicaltrials.gov is in
Link to Karen's Facebook post
[Post published on 10/26/2023 by Márcio Galvão]
