NorthStrive files patents for EL-22 and EL-32 in spaceflight muscle loss
NorthStrive Biosciences, a subsidiary of NASDAQ-listed PMGC Holdings, has filed two US patent applications covering the use of its preclinical candidates EL-22 and EL-32 in preserving lean muscle mass during long-duration spaceflight. The applications, assigned US Patent Application Nos. 19/774,556 and 19/774,575, were filed on 21 August 2026 and extend the company's existing intellectual property estate into the microgravity-exposed patient population.
EL-22 is an engineered probiotic designed to target myostatin, a protein that negatively regulates skeletal muscle growth. EL-32 targets both myostatin and activin A, which serves a similar suppressive role on muscle hypertrophy. In a microgravity environment, the absence of mechanical loading causes skeletal muscle to atrophy progressively, and current countermeasures rely primarily on in-flight exercise protocols and nutritional support. NorthStrive says it is not aware of any pharmacological agent approved by any regulatory authority specifically for microgravity-induced muscle loss, and it believes an orally deliverable approach would suit the practical constraints of crewed missions, where mass, cold-chain capacity and crew time are each tightly limited.
What the applications claim
The EL-22 application claims compositions comprising an isolated myostatin-derived Myo-2 peptide, multimers of up to eight such peptides, and fusion proteins pairing mature myostatin protein with those peptides. Delivery claims include oral dosage forms as well as nasal, injectable and topical preparations. The EL-32 application centres on a microorganism transformed to express both myostatin and activin A as a bispecific antigen on its cell surface, with embodiments using a lactic acid bacterium such as Lactobacillus paracasei. Both applications also claim combination approaches using apelin or ursolic acid, two compounds previously studied in the context of muscle metabolism.
NorthStrive is explicit that neither candidate has been evaluated in humans for any indication, that no clinical trial in a microgravity population is under way, and that no agreement exists with NASA, any other space agency, or any commercial space operator.
Market and competitive context
The spaceflight health market is nascent but drawing increasing interest as commercial station programmes move through development and agency objectives for lunar and Mars exploration extend planned mission durations. Longer missions translate to greater cumulative muscle loss risk, which is attracting both pharmaceutical and nutraceutical approaches. NorthStrive's primary commercial focus remains terrestrial: the company has already filed patent applications directed at muscle preservation during GLP-1 receptor agonist and obesity-related weight loss treatment, and has an exclusive licence in place covering animal health applications of the same biology.
The GLP-1 adjacency is strategically significant. Semaglutide and tirzepatide have driven rapid adoption in obesity management, and there is a growing clinical concern that significant lean muscle mass is lost alongside fat during GLP-1-induced weight loss. Several companies are pursuing muscle-sparing strategies in this patient population, ranging from selective androgen receptor modulators to myostatin inhibitors delivered as conventional biologics. NorthStrive's probiotic delivery approach, if validated clinically, would be differentiated on administration route, though the path from preclinical candidate to approved product in either the GLP-1 or spaceflight indication remains long and uncertain.
The filing of a patent application carries no guarantee that claims will be granted or that any issued patent will provide commercially meaningful protection. For an early-stage company with preclinical-only assets, the breadth of the IP strategy signals commercial ambition, but investors should note that no human data underpins either candidate in any indication at this stage.