Laboratory Tests Recommended Prior to Initiating Kesimpta (Ofatumumab) Therapy
Before starting Kesimpta (ofatumumab), patients should undergo comprehensive screening with complete blood count, hepatitis B testing, and tuberculosis screening to prevent serious complications.
Required Baseline Laboratory Tests
Complete blood count (CBC) with differential to establish baseline hematologic parameters and detect any pre-existing cytopenias, as ofatumumab can cause severe cytopenias including neutropenia, thrombocytopenia, and anemia 1
Hepatitis B virus (HBV) screening including:
- Hepatitis B surface antigen (HBsAg)
- Hepatitis B core antibody (anti-HBc)
- Hepatitis B surface antibody (anti-HBs) if indicated
This screening is critical as HBV reactivation can occur with ofatumumab, potentially resulting in fulminant hepatitis, hepatic failure, and death 1
Tuberculosis screening with either:
- Quantiferon TB Gold test, or
- Tuberculin skin test (TST)
This is especially important for patients with prior TB exposure or from regions with high TB prevalence 2
Liver function tests including:
- AST/ALT (transaminases)
- Alkaline phosphatase
- Bilirubin
These tests establish baseline liver function prior to initiating therapy that may affect the liver 3
Renal function tests including:
- Blood urea nitrogen (BUN)
- Serum creatinine
- Estimated glomerular filtration rate (eGFR)
These tests help assess baseline kidney function 3
Pregnancy test for women of childbearing potential before starting therapy 3
Additional Recommended Tests
Immunoglobulin levels (IgG, IgM) to establish baseline values, as B-cell depleting therapies may affect immunoglobulin production over time 4
Serum electrolytes including sodium, potassium, calcium, and magnesium to establish baseline values 3
Vaccination status review - patients should receive any needed vaccinations, particularly live vaccines, prior to starting ofatumumab as B-cell depleting therapy may reduce vaccine effectiveness 2
Monitoring During Treatment
After initiating Kesimpta, patients should be monitored for:
Complete blood counts at regular intervals to detect potential cytopenias 1
Signs and symptoms of infection as ofatumumab can increase infection risk 1
Clinical and laboratory signs of hepatitis or HBV reactivation for several months following treatment, especially in patients with evidence of current or prior HBV infection 1
Important Considerations
For patients who show evidence of hepatitis B infection (HBsAg positive or HBsAg negative but anti-HBc positive), consultation with physicians experienced in managing hepatitis B is recommended regarding monitoring and consideration for HBV antiviral therapy 1
Patients with evidence of current or prior HBV infection should be monitored for clinical and laboratory signs of hepatitis or HBV reactivation during and for several months following treatment 1
If HBV reactivation occurs while receiving ofatumumab, immediately discontinue the medication and institute appropriate treatment 1
Monitor for signs of progressive multifocal leukoencephalopathy (PML), a rare but serious potential complication 1