e19514 Background: Tal, a bispecific antibody targeting CD3 and GPRC5D receptors, has shown high response rates in heavily pretreated R/R MM patients. This study aimed to evaluate adverse events (AEs), specifically dysgeusia and weight loss in MM patients treated with tal. Methods: Patients treated at the University of Arkansas for Medical Sciences who received at least one dose of tal were included. Common Terminology Criteria for Adverse Events (CTCAE) was used to grade AEs. The body mass index (BMI)-adjusted weight loss grading system (WLGS) was used to capture weight loss trends over duration of treatment. Weight loss based on BMI was graded based on the BMI-WLGS. Results: 17 patients were included in our analysis. Nine patients (53%) were male. Ten patients (59%) were African American. Median age at diagnosis was 62 (range: 51-75years). Six patients (35%) had Eastern Cooperative Oncology Group (ECOG) performance status ≥2. The median number of prior lines of therapy was seven (range: 3-12). Fourteen patients (82%) received at least one prior autologous hematopoietic stem cell transplant. The median number of tal doses received was 14.8 (range: 2-29). Median time on treatment (ranging from 1.15 to 15.84) was 4.36 months (range: 1.2-15.8 months). Overall response rate (ORR) for was 76%. Cytokine release syndrome occurred in 12 patients (70.6%), with 5 patients (29.4%) in grade 2 or higher CRS. Immune effector cell-associated neurotoxicity syndrome (ICANS) in four patients (23.6%), and 2 patients (11.8%) had grade 2 ICANS. Fourteen patients (82%) developed significant weight loss during treatment with tal. The median weight loss was 11.6 lbs., and median decrease in BMI was 1.85. Median percentage of weight loss was 6.1% from weight prior to tal ranging from 0% to 14.3%. Two patients had grade I, five patients had grade II, six patients had grade III, and one patient had grade IV weight loss per the BMI-WLGS grading system. Fourteen patients (82%) reported dysgeusia during tal treatment. Eight of these patients had grade I dysgeusia, and six patients had grade II dysgeusia. Two patients had persistent dysgeusia even after discontinuation of tal treatment at time of last follow up. Eight patients had weight gain after tal discontinuation (n = 8/14, 57%), with 5 returning to their baseline weight or higher. Six of these patients had dysgeusia during tal, and all six had resolution of dysgeusia after tal discontinuation. Conclusions: In this study, tal resulted in weight loss and dysgeusia in the majority of patients with most cases of dysgeusia resolving after tal discontinuation. Patients, on average, lost 6% of their initial weight during tal treatment. More than two-thirds of patients treated with tal developed BMI-adjusted WLGS grade ≥II. Weight loss persisted in approximately half of the patients after discontinuation of tal. Such AEs need to be discussed with patients and monitored during treatment.