A series of articles on natalizumab were published which give practical advice for this drug which clinicians often turn to when ‘running out of options’ (Gastroenterol Hepatol 2012; 8: 4-17).
Slides from these articles should be available soon (not online on 1/2/13):
According to an algorithm on page 7, in patients with moderate-severe Crohn’s disease who have failed conventional therapies and anti-TNF drugs (or unable to tolerate), the next step is to obtain anti-JCV (John Cunningham Virus) antibody status. Patients who test negative are ‘Okay to treat with natalizumab’ due to very low risk of progressive multifocal leukoencephalopathy (PML). Repeated testing at least once a year is then recommended.
For patients who test positive for anti-JCV at any time point, natalizumab can be considered if no other treatment options are available, but the risk of PML is much greater. Previous blog entries (below) have discussed this in greater detail and have provided additional references:
- Quantifying Risk of PML with Natalizumab | gutsandgrowth
- Vedolizumab -another new IBD treatment | gutsandgrowth
Another article published the experience in 36 Mayo clinic patients between April 2008-September 2010 (Inflamm Bowel Dis 2012; 18: 2203-08). Consecutive patients who received natalizumab were prospectively followed. Of the 36 treated with natalizumab, 30 agreed to participate in the study. 23 patients had failed two anti-TNF agents and 7 had failed one anti-TNF agent. Median age was 35 years.
- 14 (46%) had a complete clinical response, 12 had a partial response, and four had no response. Cumulative probability of a complete response within 1 year was 56%.
- Time to response: 10% after 1st dose, 50% of patients had complete response after 4th dose
- Adverse events were common –though this rarely caused drug cessation. Common events included headache and infections (listed in Table 4 of article). Some infections prompted holding natalizumab for up to 8 weeks.
- 11 stopped natalizumab due to lack of improvement.