Real-world Outcomes of Nusinersen or Onasemnogene Abeparvovec (OA) Monotherapy, or Switching to OA from Nusinersen in SMA Patients Aged ≥6 Months (P7-9.001)

Abstract

<h3>Objective:</h3> We sought to describe real-world clinical outcomes and health care resource utilization (HCRU) in US patients with SMA aged ≥6 months when treated with nusinersen monotherapy, OA monotherapy, or switched to OA from nusinersen. <h3>Background:</h3> Disease-modifying treatments including nusinersen and OA have substantially improved SMA prognoses, but real-world data on treatment outcomes and HCRU are limited. <h3>Design/Methods:</h3> We conducted a retrospective chart review with outcomes summarized descriptively for patients at or before the index date (date of monotherapy initiation or switch to OA) who had medical information available for ≥1 follow-up visit. HCRU was summarized per patient-year (PPY). <h3>Results:</h3> This analysis included 55 patients (19 nusinersen monotherapy; 21 OA monotherapy; 15 switching to OA from nusinersen). SMA phenotypes were type 1 (8/19; 4/21; 12/15), type 2 (8/19; 9/21; 1/15), type 3 (3/19; 5/21; 0/15), and undetermined (0/19; 3/21; 2/15), respectively. Improvement/maintenance of motor milestones from index was achieved by 8/19, 12/19, and 7/14 patients, respectively. Mean time to improvement (±SE) was 5.8 (1.4), 2.0 (0.4), and 4.7 (1.0) months, respectively. For patients treated with nusinersen monotherapy, OA monotherapy, or switching to OA from nusinersen, 12/19, 20/21, and 8/14 achieved/maintained normal cry function; 12/14, 18/18, and 9/11 improved/maintained speech function; and 10/17, 18/19, and 7/14 improved/maintained any eating function (e.g., thin liquids by mouth, some food consistency by mouth), respectively. Inpatient admission rates at baseline vs. follow-up were 1.06 vs. 0.65, 0.34 vs. 0.00, and 1.69 vs. 0.74; emergency room visits were 1.09 vs. 0.54, 0.26 vs. 0.34, and 1.25 vs. 0.50 PPY, respectively. <h3>Conclusions:</h3> Patients with SMA improved/maintained function across multiple outcomes after receiving OA at ≥6 months of age, regardless of prior nusinersen therapy. Time-to-improvement for developmental milestones was shortest for patients who received OA monotherapy. Patients also experienced reductions in the rate of inpatient admissions, with no admissions after OA monotherapy. <b>Disclosure:</b> Dr. Dabbous has received personal compensation for serving as an employee of NOVARTIS GENE THERAPIES, INC.. Dr. Dabbous has stock in NOVARTIS GENE THERAPIES, INC. Min Yang has nothing to disclose. Mihaela Georgieva has nothing to disclose. Walter Toro has received personal compensation for serving as an employee of Astellas. Walter Toro has received personal compensation for serving as an employee of Avexis. Walter Toro has received personal compensation for serving as an employee of Novartis Gene Therapies. Ms. LaMarca has received personal compensation for serving as an employee of Novartis Gene Therapies. Anish Patel has nothing to disclose. Miss Anderson has nothing to disclose. Ms. Akbarnejad has nothing to disclose. Dr. Reyna has received personal compensation for serving as an employee of Novartis Gene Therapies.