Ofatumumab (Arzerra) and Weight Loss
Ofatumumab (Arzerra) is not associated with weight loss or difficulty losing weight, as it is a monoclonal antibody used primarily for chronic lymphocytic leukemia (CLL) treatment with no documented effects on weight regulation.
What is Ofatumumab (Arzerra)?
- Ofatumumab is a fully human anti-CD20 monoclonal antibody that binds to B-lymphocytes expressing CD20 cell surface antigens 1
- It was approved by the FDA for the treatment of chronic lymphocytic leukemia (CLL) in patients who are refractory to fludarabine and alemtuzumab-based regimens 1, 2
- The medication works by producing complement-dependent cell lysis and antibody-mediated cell cytotoxicity in cells expressing CD20 1
Side Effects of Ofatumumab
- The most common side effects of ofatumumab include infusion reactions, neutropenia, and increased risk for infection 1
- Other reported adverse effects include anemia, rash, fever, and diarrhea 2
- Weight loss or difficulty losing weight is not listed among the documented side effects of ofatumumab 1, 2
Medications That May Affect Weight
For context, several medications are known to affect weight management:
- Medications associated with weight gain include insulin secretagogues, thiazolidinediones, and insulin 3
- Medications that are generally weight neutral include dipeptidyl peptidase 4 inhibitors 3
- Medications that may promote weight loss include metformin, α-glucosidase inhibitors, sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide 1 agonists, and amylin mimetics 3
FDA-Approved Weight Loss Medications
For patients concerned about weight management:
- FDA-approved medications for long-term weight management include phentermine/topiramate ER, lorcaserin, naltrexone/bupropion ER, orlistat, and GLP-1 receptor agonists like semaglutide and liraglutide 3
- These medications are typically indicated for patients with BMI ≥27 kg/m² with weight-related comorbidities or BMI ≥30 kg/m² 3
- Recent studies show significant weight loss with newer agents like semaglutide (14.9-16.0% at 68 weeks) and tirzepatide (15.0-20.9% at 72 weeks) 3
Clinical Implications
- When choosing medications for patients concerned about weight, it's important to consider their effect on weight management 3
- For patients with chronic conditions requiring medication, whenever possible, minimize medications associated with weight gain 3
- Ofatumumab is a specialized treatment for CLL and does not have documented effects on weight regulation 1, 2
Conclusion
Patients taking ofatumumab (Arzerra) should not experience difficulty losing weight due to the medication itself, as it has no known mechanisms or documented effects on weight regulation. If weight changes occur while on ofatumumab, other factors should be investigated.