In April, the FDA issued a notable drug approval, a complete response letter (CRL), and several pipeline updates spanning rare neurologic disorders, neurodegenerative disease, and device-based therapeutics. This roundup highlights some of these actions. For information on approvals in other specialties during the first quarter of 2026, see the Medscape Medical News FDA Drug Approvals page.

Gene Therapy for Sanfilippo Syndrome Type A Moves Forward

On April 2, the FDA accepted the resubmitted biologics license application for UX111 (rebisufligene etisparvovec), an investigational AAV9-based gene therapy targeting Sanfilippo syndrome type A. The drug’s manufacturer, Ultragenyx, announced a new Prescription Drug User Fee Act action date of September 19, 2026. The resubmission follows a prior CLR that primarily cited issues related to chemistry, manufacturing, and controls vs clinical efficacy. If approved, UX111 could become the first disease-modifying treatment for this rare, progressive neurodegenerative disorder.

FDA Clears Wearable TAPS Device for Tremor

Cala kIQ Plus, an updated wearable neuromodulation system for essential tremor (ET) and Parkinson’s disease (PD)-related tremor, was cleared by the FDA on April 15, manufacturer Cala announced in a statement. The device, a transcutaneous afferent patterned stimulation (TAPS) system, incorporates adaptive calibration and three customizable therapy modes to personalize treatment delivery for ET as well as postural and kinetic hand tremor symptoms in PD.

FDA clearance of Cala kIQ Plus was based on data presented at the American Academy of Neurology (AAN) 2026 Annual Meeting and reported by Medscape Medical News.

Intravenous (IV) Nimodipine for Aneurysmal Subarachnoid Hemorrhage (aSAH) Receives CRL

The FDA issued a CRL on April 23 to Grace Therapeutics, the manufacturer of an experimental treatment for patients with aSAH, the company reported. GTx-104 is an IV formulation of nimodipine that is intended to improve delivery consistency compared with oral nimodipine, and potentially reduce risks related to food effects, drug-drug interactions, and dosing errors.

In the CRL, the FDA identified deficiencies related to chemistry, manufacturing, and controls and nonclinical sections of the application, including concerns related to packaging-related leachables, toxicology risk assessments, and manufacturing processes. The company reported that it plans to request a Type A meeting with the FDA to clarify a path forward for the drug.

First Non-Antipsychotic for Alzheimer’s-Related Agitation Approved

The first-in-class oral non-antipsychotic for Alzheimer’s disease (AD)-related agitation received FDA approval on April 30. Dextromethorphan hydrobromide and bupropion hydrochloride (Auvelity; Axsome Therapeutics) is the second FDA-approved drug for this indication; the antipsychotic brexpiprazole (Rexulti; Otsuka Pharmaceutical) was cleared in 2023. The new fixed-dose combination drug has a novel mechanism of action: Dextromethorphan targets N-methyl D-aspartate and sigma-1 receptors, while bupropion inhibits CYP2D6 to sustain therapeutic levels of dextromethorphan, modulating pathways involved in agitation and behavioral symptoms in neurodegenerative disease.

As previously reported by Medscape Medical News, the supplemental new drug application for Auvelity (formerly known as AXS-05) was based on the phase 3 ADVANCE-1 and ACCORD-2 trials, which demonstrated significant reductions in agitation severity compared with placebo.