Tenaya Therapeutics Gets Go-Ahead for HCM Gene Therapy Trial

Tenaya Therapeutics announced on Monday that they have received FDA clearance to begin a Phase 1 clinical trial of targeted gene therapy for HCM.

Tenaya is developing TN-201, a first in class adeno-associated virus based therapy being developed to treat HCM caused by mutation(s) in the MYBPC3 gene. They anticipate that the trial will begin in the third quarter of 2023. The therapy delivers one fully functional MYBPC3 gene to the patient via injection with a deactivated virus. Tenaya hopes that this therapy will restore normal levels of the MYBPC3 protein, thereby halting disease progression, and even potentially reversing the course of the disease, after just a single treatment.

The TN-201 Phase 1b clinical trial will be a multi-center, open-label study designed to assess the safety of an intravenous infusion of TN-201. They hope to enroll at least 6 symptomatic, non-obstructive HCM patients who carry the MYBPC3 gene and who already have received an automatic implantable cardioverter defibrillator (ICD) as part of their treatment plan to date.

You can read the full  press release here.

Stay tuned to HCMBeat for updates!

HCM Genes Common in General Population

A recent study sought to find how common genetic cardiomyopathies are in the general population. 

By studying United Kingdom Biobank samples from 200,643 people who had undergone complete genetic sequencing, researchers established that genes linked to HCM are found in one out of every 149 people! 

More than half of those identified as having a HCM gene had a mutation in the MYBPC3 gene, making it the most common HCM gene in this sampling.

Gene Therapy for HCM

A recent article on Biospace.com describes a method of targeted gene therapy for HCM patients currently being developed by Tenaya Therapeutics. This therapy is intended for patients whose HCM is caused by a mutation in the MYBPC3 gene.

According to Tenaya CEO Faraz Ali, animal models show that this therapy can reverse declining heart function.

You can find more information on about Tenaya’s approach here.

Targeted Gene Therapy for HCM

The expanding field of personalized medicine has not left hypertrophic cardiomyopathy behind. In fact, two companies are currently developing targeted gene therapies for HCM patients. Each therapy targets a separate and distinct HCM gene mutation.

Tenaya Therapeutics, located in the San Francisco area, is developing a therapy called TN-201 which is directed at mutations in the Myosin Binding Protein C3 (MYBPC3) gene. The therapy has shown favorable results in mice.  In May of this year, Tenaya received Orphan Drug Designation from the U.S Food and Drug Administration. An Orphan Drug Designation confers certain tax and economic incentives on companies developing a treatment for rare conditions.

Meanwhile, this week, Lexeo Therapeutics acquired Stelios Therapeutics, a San Diego based company developing a therapy for HCM patients with a mutation in the TNNI3 gene. These TNNI3 patients comprise somewhere between 5% and 7% of all patients with HCM, or approximately 30,000 people.  The underpinnings of this research come from the University of California, San Diego.

HCMBeat will continue following these developments. It is a busy and exciting time in the treatment of HCM!

Are Your Genetic Test Results Valid?

A recent study by several HCM genetics researchers around the globe, led by Australia’s Dr. Jodie Inglesfound that 2/3 of genetic mutations previously reported to patients as HCM causative may actually NOT trigger HCM.

Continue reading “Are Your Genetic Test Results Valid?”

CRISPR Eliminates HCM Gene !

Scientists, in a follow up to three earlier, less successful, Chinese experiments, have for the first time used a recently developed gene editing process known as “CRISPR” to remove a genetic defect from a human embryo.  The specific defect that the scientists targeted was a mutation in MYBPC3, a common genetic cause of hypertrophic cardiomyopathy (HCM).

What Happened in the Study?

The study authors consisted of a multi-national team of geneticists, cardiologists, fertility experts and embryologists.  Led by Dr. Shoukhrat Mitalipov of Oregon Health Sciences University, in collaboration with researchers at the Salk Institute in La Jolla, CA, China and South Korea, the researchers were able to largely remove the HCM gene MYBPC3 from very early stage human embryos.

Their research involved using eggs from 12 healthy female donors, and sperm from a male HCM patient with the MYBPC3 gene.  When gene-editing components were introduced to the egg along with the sperm, prior to fertilization of the egg, approximately 3/4 of the embryos repaired themselves using the DNA blueprint provided by the normal, non-mutated copy of the gene from the unaffected female.  This was somewhat surprising to researchers, who had theorized that cells would replicate using a blueprint from the repaired paternal gene – not the healthy gene of the mother.

Ultimately, genes were corrected in 42 of 58 embryos, constituting 72.4% of the total, a higher proportion than expected, and far more than any correction shown in previous experiments.

Implications for the Future

This technique is still far from general usage and will require further study and refinement.  And, currently it is not legal in the United States since the Food & Drug Administration currently prohibits medical gene editing which would impact future generations.

However, it would be possible for this technique to be used alongside current technology to assist families with genetic diseases like HCM.  If used in conjunction with pre-implantation genetic testing and in-vitro fertilization (PGD), the technique could repair the large proportion of embryos (roughly 50%) which must be discarded due to genetic defectiveness.

While there are critics who say that this technology will lead to “designer babies” and that it creates troubling ethical issues for society, most HCM patients believe that it provides a ray of hope, so that hopefully one day, in the not-too-distant-future, our children and grandchildren will be free of the affliction that has permeated our lives, as well as the lives of our siblings, our parents, our aunts and uncles, our cousins, our grandparents, and our great-grandparents.

Story Links:

As this story was reported by all major news sources, links to many of the articles can be found below.

Nature

The Atlantic

New York Times

Washington Post.

NPR

LA Times

Los Angeles Times – Q&A video clip with lead study author Shourkhrat Mitalipov

The Guardian

USA Today

MIT Technology Review

Gizmodo

Boston Herald

LA Times article regarding ethics -response to first article

NOTE THAT APPROXIMATELY A MONTH AFTER THE PUBLICATION OF THIS ARTICLE, THE RESULTS HAVE BEEN CALLED INTO QUESTION BY OTHER SCIENTISTS.

See this article in MIT Technology Review, this article in Science Magazinethis article in Nature, and this article in The Scientist, all of which cite this article in BioRxiv which poses alternative theories for the results claimed by the original paper.

HCM May Develop Later in Life

A recent study followed 14 patients carrying one of two known genes associated with HCM (MYBPC3 and MYH7) over a 10+ year period .  At the time  of gene identification, none of the patients shown clinical evidence of hypertrophy.  Over the time span of the study, 3 patients, who were then adults, had developed signs of HCM.  Hence, the study suggests that periodic screenings are necessary for gene positive individuals throughout adulthood.

According to Cardiomyopathy U.K., the researchers undertook this project due to the lack of information and guidelines available to patients who are gene positive but have no outward signs of the disease.