Comparison of DaxibotulinumtoxinA-lanm (Daxi) Versus OnabotulinumtoxinA (BtxA) for Adductor Type Laryngeal Dystonia (AdLD)

ObjectivesBotulinum toxin A (BtxA) injection for AdLD is typically performed approx. 3 months. DaxibotulinumtoxinA-lamn (Daxi) is a peptide-formulated neuromodulator with reported longer therapeutic duration. This study compared safety and efficacy of Daxi to historical BtxA results in AdLD patients. MethodsIn this open-label, prospective clinical trial, 22 stable-dose, BtxA-responsive AdLD patients underwent Daxi injection using manufacturers dosing conversion. To optimize safety, the first 10 patients doses were given in staged fashion (3-6 days between half doses). Safety and duration of voice benefit (DVB) were the primary outcomes. PROMs and voice analyses were obtained pre- and monthly post-injection. ResultsOf 22 patients, 20 (75 percent female, mean age= 58.3) were analyzed, with two excluded for injection (misses). No adverse reactions were reported. EAT-10 showed no difference pre- and post-Daxi injection (p=0.068). VHI-10 significantly improved (p=0.004) pre- to post-injection. Procedural LEMG quantitative data for Daxi and BtxA were comparable (p=0.279). DVB of Daxi was longer than BtxA in 8/20 (40 percent), equal to BtxA in 7/20 (35 percent), and shorter than BtxA in 5/19 (25 percent). Those with Daxi benefit had on average 43.9 percent (39.5 days) longer therapeutic duration than their previous BtxA treatments. 8 patients (36.4 percent) returned to BtxA at subsequent injection whereas 13 patients (59.1 percent) desired repeat Daxi injection. ConclusionThis study represents the first use of Daxi for AdLD. Daxi was notably safe and effective, with 40 percent of patients reporting substantive longer duration of voice benefit than with BtxA. Mean duration of voice benefit was 43.9 percent longer than their previous BtxA treatments.