When I highlighted the risk of hypogammaglobulinaemia and infection in MSers receiving anti-CD20 therapy after ECTRIMS I go a very long email from someone from Roche playing down the risks. The following study is therefore very timely and shows that when comparing interferon-beta, glatiramer acetate, natalizumab, fingolimod and rituximab with each other it is rituximab that comes out worst in relation to infectious complications.
You also need to remember that not all anti-CD20 therapies are made equal and that ocrelizumab is a more potent B-cell depleter than rituximab. We know this based on the infectious complications seen in study subjects with rheumatoid arthritis and lupus and the observation that there is a clear varicella-zoster signal in the ocrelizumab phase 3 programme. In this context, an interesting observation was that there was a lower rate of anti-herpes/anti-virals in the rituximab-treated MSers compared to the other DMTs. This is interesting and raises questions of why this should be? Could it be because rituximab only reduces the CD8+ T-cell counts by about 15% after the first infusion and his little impact thereafter?
So don’t let anyone pull the wool over your eyes that anti-CD20 therapies are not immunosuppressive and are not associated with an infection signal. It is becoming clear to me that continuous dosing with anti-CD20 therapy will result in a cumulative increase in infections and at some stage we are as an MS community are going to have to derisk this problem by using (1) anti-CD20 therapy as an immune-reconstitution therapy (IRT) or as (2) an induction agent or (3) by correcting the immune deficiency by giving immunoglobulin replacement therapy when our patients develop hypogammaglobulinaemia.
I think we need to do the ADIOS study sooner than later. Don’t you?
Gustavo et al. Infection Risks Among Patients With Multiple Sclerosis Treated With Fingolimod, Natalizumab, Rituximab, and Injectable Therapies. JAMA Neurol. Published online October 7, 2019. doi:10.1001/jamaneurol.2019.3365
Question: What is the risk of infections in association with different disease-modifying treatments for multiple sclerosis?
Findings: This nationwide cohort study found that patients with multiple sclerosis are at a generally increased risk of infections, and this risk is partly dependent on the choice of treatment. The rate of infections was lowest with injectable therapies; among newer treatments, use of rituximab was associated with the highest rate of serious infections but less use of herpes antiviral medications compared with fingolimod and natalizumab.
Meaning: Per the results of this study, physicians and patients should be aware of infection risks associated with newer multiple sclerosis treatments and perhaps particularly anti-CD20 therapies.
Importance: Although highly effective disease-modifying therapies for multiple sclerosis (MS) have been associated with an increased risk of infections vs injectable therapies interferon beta and glatiramer acetate (GA), the magnitude of potential risk increase is not well established in real-world populations. Even less is known about infection risk associated with rituximab, which is extensively used off-label to treat MS in Sweden.
Objective: To examine the risk of serious infections associated with disease-modifying treatments for MS.
Design, Setting, and Participants: This nationwide register-based cohort study was conducted in Sweden from January 1, 2011, to December 31, 2017. National registers with prospective data collection from the public health care system were used. All Swedish patients with relapsing-remitting MS whose data were recorded in the Swedish MS register as initiating treatment with rituximab, natalizumab, fingolimod, or interferon beta and GA and an age-matched and sex-matched general population comparator cohort were included.
Exposures: Treatment with rituximab, natalizumab, fingolimod, and interferon-beta and GA.
Main Outcomes and Measures: Serious infections were defined as all infections resulting in hospitalization. Additional outcomes included outpatient treatment with antibiotic or herpes antiviral medications. Adjusted hazard ratios (HRs) were estimated in Cox regressions.
Results: A total of 6421 patients (3260 taking rituximab, 1588 taking natalizumab, 1535 taking fingolimod, and 2217 taking interferon beta/GA) were included, plus a comparator cohort of 42 645 individuals. Among 6421 patients with 8600 treatment episodes, the mean (SD) age at treatment start ranged from 35.0 (10.1) years to 40.4 (10.6) years; 6186 patients were female. The crude rate of infections was higher in patients with MS taking interferon beta and GA than the general population (incidence rate, 8.9 [95% CI, 6.4-12.1] vs 5.2 [95% CI, 4.8-5.5] per 1000 person-years), and higher still in patients taking fingolimod (incidence rate, 14.3 [95% CI, 10.8-18.5] per 1000 person-years), natalizumab (incidence rate, 11.4 [95% CI, 8.3-15.3] per 1000 person-years), and rituximab (incidence rate, 19.7 [95% CI, 16.4-23.5] per 1000 person-years). After confounder adjustment, the rate remained significantly higher for rituximab (HR, 1.70 [95% CI, 1.11-2.61]) but not fingolimod (HR, 1.30 [95% CI, 0.84-2.03]) or natalizumab (HR, 1.12 [95% CI, 0.71-1.77]) compared with interferon beta and GA. In contrast, use of herpes antiviral drugs during rituximab treatment was similar to that of interferon beta and GA and lower than that of natalizumab (HR, 1.82 [1.34-2.46]) and fingolimod (HR, 1.71 [95% CI, 1.27-2.32]).
Conclusions and Relevance: Patients with MS are at a generally increased risk of infections, and this differs by treatment. The rate of infections was lowest with interferon beta and GA; among newer treatments, off-label use of rituximab was associated with the highest rate of serious infections. The different risk profiles should inform the risk-benefit assessments of these treatments.
In response to a comment, the following figures put the serious infection (requiring hospitalisation) risk on ocrelizumab in context; i.e. how common is this complication. The overall figure is 2.24 serious infections per 100 patient-years. In other words for every 45 patients on ocrelizumab for 12 months 1 patient will be admitted to hospital with a serious infection.
However, if you develop low IgG levels (hypogammaglobulinaemia) the risk rises to 5.48 serious infections per 100 patient-years or for every 18 patients on ocrelizumab for 12 months 1 patient will be admitted with a serious infection. This is why we are now monitoring peripheral blood immunoglobulin levels on an annual basis in all our patients on anti-CD20 therapy.
MD Here I add this to the bottom of ProfGs post
Evaluating the efficacy and safety of ZytuxTM (Rituximab, AryoGen pharmed) in Iranian multiple sclerosis patients: An observational study. Naser Moghadasi A, Darki A, Masoumi P, Hashemi SN, Ghadiri F. Mult Scler Relat Disord. 2019 Sep 27;36:101419
BACKGROUND:Anti-CD20 monoclonal antibodies such as ocrelizumab, rituximab, and ofatumumab target B-cell lineage. Clinical trials have demonstrated their effect on reducing both magnetic resonance imaging (MRI) active lesion burden as well as clinical activity. Zytux™ (Rituximab, AryoGen Pharmed) used in the present study for multiple sclerosis (MS) patients is basically a biosimilar rituximab. In this observational study, a total of 100 patients receiving Zytux™ were collected to see its effect on the clinical course of the disease.
RESULT: A total of 100 MS patients including 36 males and 64 females participated in the present study. The patients included 20 relapsing remitting MS (RRMS), 20 primary progressive MS (PPMS), and 60 secondary progressive MS (SPMS) patients. Totally, the mean of EDSS score before and after the administration of drug was 5.50 ± 1.04 (ranging from 1 to 7) and 5.11 ± 1.59 (ranging from 0 to 7), respectively, with the difference between them being very significant (p-value: 0.000). Also, the mean of ARR before and after the initiation of the medication was 0.47 and 0.10, respectively, whose difference was also significant (p-value: 0.000). In our study, the greatest effect of Zytux™ was observed in RRMS patients. At the time of injection, 70 patients indicated some reactions including limb pain, skin sensitivity, and throat irritation. One month after the injection, one of the patients suffered from pneumonia and two patients had a urinary tract infection.
CONCLUSION:The observed results revealed that the Zytux™ could have a positive and significant effect on all types of MS