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FDA Decisions Expected: February 2026

Your monthly synopsis of new drugs expected to hit the market 

January 15, 2026

Drug pipeline for February 2026

At Prime Therapeutics (Prime), we have positioned ourselves to best prepare our clients to manage new drugs. Our clinical and trade relations teams keep a keen eye on drugs awaiting approval by the United States (U.S.) Food and Drug Administration (FDA).
Feb. 8, 2026: clemidsogene lanparvovec (RGX-121) 
Nippon Shinyaku and Regenxbio are awaiting FDA approval of the gene therapy RGX-121 for the treatment of patients with mucopolysaccharidosis II (MPS II), also known as Hunter syndrome. MPS II is a rare, genetic, metabolic condition that almost exclusively affects boys. MPS II is characterized by tissue damage in many organ systems in the body including the airway, heart, liver, spleen, eyes, skin, bones and joints. Interim data from the open-label CAMPSIITE trial revealed that eight out of 10 patients enrolled in the trial achieved the surrogate endpoint of reduction in D2S6 levels in the cerebrospinal fluid (CSF).³ RGX-121 is administered as a one-time intracisternal injection using guided imagery. If approved, RGX-121 will be the first gene therapy to treat MPS II. It was granted Fast Track, Orphan Drug, Rare Pediatric Disease and Regenerative Medicine Advanced Therapy designations and a Priority Review and is seeking an Accelerated Approval.

For more information, see the clemidsogene lanparvovec Deep Dive in the July 2025 edition of Prime’s Quarterly Drug Pipeline.
Feb. 8, 2026: idebenone
Idebenone is a short-chain benzoquinone, designed to preserve, protect and reactivate retinal ganglion cell function that is associated with Leber hereditary optic neuropathy (LHON), an inherited mitochondrial disorder that leads to severe vision loss. The FDA has granted a Priority Review for the treatment of LHON as well as an Orphan Drug designation. Idebenone is administered orally three times a day. The double-blind, placebo-controlled RHODOS trial did not meet its primary endpoint of best recovery in visual acuity (VA) at 24 weeks. However, statistically significant improvements were observed with the key secondary endpoint of change in best VA. In the Phase 4, open-label LEROS trial, among patients with LHON who started idebenone treatment within one year of symptom onset, 42.3% of eyes achieved clinically relevant benefit compared to 20.7% of eyes in the natural history group (odds ratio, 2.29; p=0.002). Benefit was sustained at 24 months.
 
For more information, see the idebenone Deep Dive in the January 2026 edition of Prime’s Quarterly Drug Pipeline.
Feb. 8, 2026: navepegritide (TransCon CNP)
Ascendis is awaiting an FDA decision for navepegritide, a prodrug of C-type natriuretic peptide (CNP), for the treatment of achondroplasia. The FDA granted navepegritide a Priority Review and Orphan Drug designation. In the double-blind, placebo-controlled ApproaCH trial, navepegritide administered subcutaneously once weekly demonstrated a statistically significant greater change from baseline in the primary endpoint of annualized growth velocity (AGV) with navepegritide compared to placebo at 52 weeks (AGV, 5.89 versus 4.41 cm/year, respectively; least square mean difference, 1.49 cm/yr; p<0.0001) in the overall population.⁵ If approved, navepegritide will be the second CNP available in the United States to increase linear growth in children with achondroplasia. It will compete with vosoritide (Voxzogo) and provide a once-weekly dosing option compared to Voxzogo which is administered once daily.
 
For more information, see the navepegritide Deep Dive in the October 2025 edition of Prime’s Quarterly Drug Pipeline.
Feb. 21, 2026: milsaperidone
Vanda Pharmaceuticals submitted the atypical antipsychotic agent milsaperidone to the FDA for the treatment of bipolar I disorder and schizophrenia. Milsaperidone is an active metabolite of Vanda’s iloperidone (Fanapt) that interconverts to iloperidone when administered orally. Fanapt is FDA approved for bipolar I disorder and schizophrenia and is taken orally twice daily. Milsaperidone has shown bioequivalence to iloperidone in single and multiple dose studies.⁴