Does Kesimpta (Ofatumumab) Cause Dairy Intolerance?
There is no evidence that Kesimpta (ofatumumab) causes dairy intolerance. Based on the available medical literature and clinical guidelines, dairy intolerance is not listed as a side effect of ofatumumab therapy.
Understanding Ofatumumab (Kesimpta)
Ofatumumab is a fully human anti-CD20 monoclonal antibody that targets B cells and is approved for treatment of:
- Relapsing forms of multiple sclerosis (MS)
- Previously used in certain lymphomas and chronic lymphocytic leukemia
The medication works by binding to the CD20 protein on B lymphocytes, leading to B-cell depletion through several mechanisms:
- Antibody-dependent cellular cytotoxicity
- Complement-dependent cytotoxicity
- B-cell lysis
Known Side Effects of Ofatumumab
The documented side effects of ofatumumab include:
- Injection-related reactions (20% of patients), mostly mild to moderate 1, 2
- Infections such as nasopharyngitis, upper respiratory tract infections, and urinary tract infections 2
- Headache 2
- Fever/chills (48% during initial application) 3
- Limb pain (45% during initial application) 3
In clinical trials, these side effects were generally manageable, with 72% of patients reporting no side effects after the initial injections 3.
Dairy Intolerance vs. Dairy Allergy
It's important to distinguish between:
Cow's milk allergy (CMA): An immunologically mediated reaction to cow's milk proteins that may involve multiple body systems 4
Cow's milk intolerance (CMI): Non-immunologic reactions to cow's milk, such as disorders of digestion, absorption, or metabolism (most commonly lactase deficiency) 4
None of the clinical guidelines or research studies on ofatumumab mention development of either dairy allergy or intolerance as a potential side effect.
Clinical Considerations
When evaluating patients on Kesimpta who develop gastrointestinal symptoms:
- Consider more common side effects of ofatumumab first
- Evaluate for other causes of new-onset gastrointestinal symptoms
- Remember that lactose intolerance typically develops due to decreased lactase enzyme production, which is not a known effect of anti-CD20 therapies
- Consider that gastrointestinal symptoms might be related to other medications, dietary changes, or concurrent conditions
Monitoring Recommendations
For patients on Kesimpta therapy:
- Monitor for common side effects like injection-related reactions and infections
- No specific monitoring for dairy intolerance is recommended based on current evidence
- If gastrointestinal symptoms develop, evaluate using standard clinical approaches rather than assuming a connection to ofatumumab
In conclusion, there is no established connection between ofatumumab (Kesimpta) treatment and the development of dairy intolerance based on the available medical literature and clinical guidelines.