Gene Therapy’s Pipeline Has a Steady Flow of More Than 2,000 Candidates

Just over 2,000 gene therapies are at some stage of development and 11 are in the preregistration phase when the clinicals trials and the drug development companies have filed for regulatory approval, according to a report issued earlier this week by the American Society of Gene and Cell Therapy and Citeline, a pharma business intelligence company.

Six of the 11 gene therapies in preregistration are U.S. therapies, according to the 54-page report, which also reviews the development and business prospects for cell and RNA therapies.

The six U.S. therapies in the regulatory review stage are Rocket Pharmaceuticals’ Kresladi (marnetegragene autotemcel, a lentiviral vector-based gene therapy for severe leukocyte adhesion deficiency-I; Abeona Therapeutics’ prademagene zamikeracel, or pz-cel, an autologous cell-based gene therapy for recessive dystrophic epidermolysis bullosa; Neurotech Pharmaceuticals’ NT-501, an encapsulated cell therapy for idiopathic juxtafoveal macular telangiectasia, an eye condition; Ultragenyx Pharmaceutical’s UX111, an adeno-associated virus vector gene therapy treatment for patients with Sanfilippo syndrome type A; Repimune Group’s vusolimogene oderparepvec, which is used combination with Opdivo (nivolumab) for the treatment of adult patients with advanced melanoma who have previously received an anti-PD1 containing regimen; and Precigen’s zopapogene imadenovec, also known as PRGN-2012, a treatment of recurrent respiratory papillomatosis.

In addition to the preregistration gene therapies, the report’s tally shows that as of the fourth quarter of 2024, 35 gene therapies were in phase 3 trials, 289 in phase 2 and 318 in phase 1. The remaining 1,424 are in the preclinical phase of development. The total tally is 2,117 gene therapies at some stage of development. That is a global count. Other than the relatively small group of gene therapies in the preregistration stage, the report does not have a country-by-country breakdown.

Cancer is the main target for gene therapies, according to this report. The proportion of gene therapy trials for nononcology indications shrunk for the first time in over a year to just less than half (49%), a reversal of a trend of the proportion of nononcology gene therapy trials increasing.

The report makes several comparisons between oncology and nononcology gene therapies. For example, it says that of the 1,053 pipeline gene therapies being developed for rare diseases, 8 of the top 10 targeted diseases were cancer. The top five were myeloma (98 gene therapies), acute myelogenous leukemia (79), non-Hodgkin’s lymphoma (79), B-cell lymphoma (74) and ovarian cancer 64).

In some taxonomies of gene therapy, CAR-T is put in a separate category, but this report puts CAR-T under the heading of gene therapy. Almost all (97%) of the CAR-T therapies under development at the end of last year were for cancer treatment with the remaining targeting scleroderma, HIV/AIDS and autoimmune disease.