Gene editing technologies are moving forward in preclinical development with innovative strategies designed to treat diseases at their root and even reverse them. However, many approaches still struggle to reach target cells or tissues – either they fail to arrive, or their efficacy is low. In vivo therapies face numerous challenges, but despite these hurdles, 2025 has marked a year of remarkable progress.

Gene editing technologies are moving forward in preclinical development with innovative strategies designed to treat diseases at their root and even reverse them. However, many approaches still struggle to reach target cells or tissues – either they fail to arrive, or their efficacy is low. In vivo therapies face numerous challenges, but despite these hurdles, 2025 has marked a year of remarkable progress.

Gene therapy has had its commercial struggles in the past year. The cost to patients is in the millions and fewer are stepping forward for treatment than companies would like. While development continues in this game-changing field, some have struggled with regulatory authorities during development while others have just stepped away altogether.

Rznomics Inc. continued South Korea’s year-end biotech rally with a ₩46.35 billion (US$31.35 million) IPO Dec. 18. Proceeds will fund Seongnam-si, South Korea-based Rznomic’s pipeline of gene therapies, built on the company’s trans-splicing ribozyme RNA Replacement Enzyme technology platform.

Viatris Inc. has announced FDA clearance of its IND application for MR-146, an Enriched Tear Film (ETF) AAV gene therapy candidate for the treatment of neurotrophic keratopathy. The company plans to initiate a phase I/II trial in patients with neurotrophic keratopathy in the first half of next year.

Rznomics Inc. continued South Korea’s year-end biotech rally with a ₩46.35 billion (US$31.35 million) IPO Dec. 18. Proceeds will fund Seongnam-si, South Korea-based Rznomic’s pipeline of gene therapies, built on the company’s trans-splicing ribozyme RNA Replacement Enzyme technology platform.

Addition Therapeutics came out of stealth mode to highlight its Precise RNA-Mediated Insertion of Transgenes (PRINT) gene therapy platform. The system is based on research of retrotransposons by Kathleen Collins’ laboratory at University of California, Berkeley, that was spun out into Addition in 2021.

Gene editing can repair mutations that prematurely halt protein synthesis, resulting in incomplete peptides that cause various diseases. However, other approaches achieve the same effect without altering the genome. Startup Alltrna Inc. has developed a strategy based on transfer RNA to bypass the premature stop codons that end early protein translation. The company already has a first clinical candidate that could treat metabolic diseases such as methylmalonemia or phenylketonuria.

Superoxide dismutase 1 (SOD1) mutations were among the first genetic causes identified in familial amyotrophic lateral sclerosis (ALS) and confer a toxic gain-of-function that drives motor neuron degeneration via protein misfolding, oxidative stress, mitochondrial dysfunction and neuroinflammation.

Gene editing can repair mutations that prematurely halt protein synthesis, resulting in incomplete peptides that cause various diseases. However, other approaches achieve the same effect without altering the genome. Startup Alltrna Inc. has developed a strategy based on transfer RNA (tRNA) to bypass the premature stop codons that end early protein translation. The company already has a first clinical candidate that could treat metabolic diseases such as methylmalonemia (MMA) or phenylketonuria (PKU).