This study is open-label and probably should be regarded as less dependable than some other kinds of studies, but the authors are maintaining that an underweight woman on Gilenya might need especially careful monitoring because of a higher risk of lymphopenia.
From PubMed, November 2, 2014:
Neurology. 2014 Oct 31.
Initial lymphocyte count and low BMI may affect fingolimod-induced lymphopenia
Warnke C1, Dehmel T1, Ramanujam R1, Holmen C1, Nordin N1, Wolfram K1, Leussink VI1, Hartung HP1, Olsson T1, Kieseier BC2.
Author information
1From the Department of Neurology (C.W., T.D., K.W., V.I.L., H.-P.H., B.C.K.), Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany; and Department of Clinical Neuroscience (R.R., C.H., N.N., T.O.), Karolinska Institute, Stockholm, Sweden.
2From the Department of Neurology (C.W., T.D., K.W., V.I.L., H.-P.H., B.C.K.), Medical Faculty, Heinrich-Heine University, Düsseldorf, Germany; and Department of Clinical Neuroscience (R.R., C.H., N.N., T.O.), Karolinska Institute, Stockholm, Sweden. bernd.kieseier@uni-duesseldorf.de.
OBJECTIVE:
To assess whether pretreatment-lymphocyte counts, treatment before fingolimod, age, sex, or body mass index (BMI) affects the risk of fingolimod-induced lymphopenia in patients with relapsing-remitting multiple sclerosis (RRMS).
METHODS:
Data were obtained from a German multicenter, single-arm, open-label study of patients with RRMS treated with fingolimod, and findings were validated in an independent Swedish national pharmacovigilance study.
RESULTS:
Four hundred eighteen patients with RRMS from Germany and 438 patients from Sweden were included. A nadir ≤0.2 × 109 lymphocytes/L was reached in 15% (95% confidence interval [CI] 12%-17%) of all 856 patients. Patients with lower starting lymphocyte counts (below 1.6 × 109/L) and patients with BMI lower than 18.5 kg/m2 (women only) were at higher risk of developing lymphopenia with values ≤0.2 × 109/L in the combined analysis, increasing the risk in these subgroups to 26% (95% CI 20%-31%) or 46% (95% CI 23%-71%), respectively. In the German cohort, infection rates were similar in patients who developed severe lymphopenia and those who did not.
CONCLUSIONS:
Our findings suggest that patients with low baseline lymphocyte counts and underweight women in which fingolimod treatment will be initiated should possibly be monitored more closely.
PMID: 25361781
The abstract can be seen
here.