Effects of inhibitors of the renin-angiotensin system on the efficacy of interferon beta-1b: a post hoc analysis of the BEYOND study.
BACKGROUND
In experimental autoimmune encephalomyelitis, inhibition of the renin-angiotensin system with angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme (ACE) inhibitors resulted in a significantly ameliorated disease course. We evaluated the effects of ARBs and ACE inhibitors on the efficacy of interferon beta-1b in patients with relapsing-remitting multiple sclerosis (RRMS).


METHODS
In this post hoc analysis of the BEYOND (Betaferon Efficacy Yielding Outcomes of a New Dose) study, clinical and MRI end points were compared between patients treated with interferon beta-1b 250 or 500 µg and concomitant ARBs or ACE inhibitors and patients treated with interferon beta-1b 250 or 500 µg only (reference group).


RESULTS
Patients in the ARB group (n = 22) tended to have a higher relapse rate (0.48 vs. 0.23, p = 0.051) and a higher number of new gadolinium-enhancing lesions (0.6 vs. 0.3, p = 0.057) than patients in the reference group. Patients in the ACE inhibitor group (n = 49) also tended to have a higher relapse rate (0.29 vs. 0.22, p = 0.357). No differences were observed for the other end points.


CONCLUSIONS
In the BEYOND study cohort, a concomitant medication with ARBs or ACE inhibitors did not have a beneficial effect in patients with RRMS treated with interferon beta-1b. As patients appeared to have a higher relapse rate, our results warrant further investigation.
Bayer HealthCare, Leverkusen, Germany.
M
M
Doerner
K
K
Beckmann
V
V
Knappertz
L
L
Kappos
H P
HP
Hartung
M
M
Filippi
P W
PW
O'Connor
B
B
Arnason
S
S
Cook
D
D
Jeffery
G
G
Comi
V
V
Limmroth
D000276:Adjuvants, Immunologic / Q000627:therapeutic use*; D057911:Angiotensin Receptor Antagonists / Q000627:therapeutic use*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D006801:Humans; D000068576:Interferon beta-1b; D016899:Interferon-beta / Q000627:therapeutic use*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy*; D012084:Renin-Angiotensin System / Q000187:drug effects*
D000276:Adjuvants, Immunologic; D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000068576:Interferon beta-1b; D016899:Interferon-beta