Concerns that people treated with CGRP-targeted monoclonal antibodies for their migraine may be at risk of developing hypertension have been strengthened by new research.
A Netherlands study recruited 211 patients treated with erenumab (70-140 mg every 4 weeks) or fremanezumab (225 mg every four weeks) at the Leiden Headache Center between January 2019 and January 2021.
It found a significant and sustained increase in systolic and diastolic blood pressure (BP) at all time points – 3, 6, 9 and 12 months after starting the mAbs – compared to baseline BP.
Systolic BP rose by about 5 mmHg and diastolic BP by about 3 mmHg.
As a result, nine patients were commenced on antihypertensive drugs. Five had documented hypertension before starting anti-CGRP treatment but none were on BP drugs at baseline.
“While, fortunately, the majority of patients did not require treatment for hypertension, we did observe a modest effect on the mean BP,” the study said.
The study, published in Neurology [link here], reported that a larger estimated effect on both systolic and diastolic BP was observed with erenumab than with fremanezumab.
“This study provides Class III evidence that anti-CGRP (receptor) antibodies increase blood pressure when used to treat patients with migraine,” it said.
The investigators said studies indicated that CGRP provides a key compensatory mechanism against hypertension.
“Thus, while a potential risk of hypertension may arise when patients are treated with CGRP blocking medication, it may be that blocking CGRP is only potentially problematic for patients already at risk of developing hypertension,” it said.
It noted that BP rises were apparent in the first weeks after the initial erenumab injection.
“This suggests that whether a patient develops hypertension, will be apparent soon after initiating treatment. At the same time, it seems that the rise in BP is a long lasting effect of treatment and no adaptation process takes place within at least 12 months.”
The study concluded that caution for raised BP with anti-CGRP treatment should be added to clinical guidelines for migraine.
“As migraine itself is associated with an increased risk for cardio- and cerebrovascular events, it is important to monitor the BP after starting treatment with CGRP targeting treatment to prevent increasing this risk.”
Australian perspective
Commenting on the study, Sydney neurologist Dr Bronwyn Jenkins told the limbic that it was good practice to check BP in all patients.
“In fact, this is usually a necessity since the antihypertensive preventive medications used in migraine would not be used if the BP doesn’t suit this. This study reiterates the information already known from other studies that vascular risk factors are particularly relevant in our population with migraine disorder.”
Dr Jenkins said the study was interesting given most reports have been in post-marketing real world use and not formally studied.
“BP was monitored during the sentinel randomised controlled trials in approximately 10,000 patients without hypertension being noticed. I would think that most neurologists and primary physicians may not be aware of the potential role of CGRP in the cardiovascular system, including BP.”
She said the small BP effect in a minority of participants would not significantly change practice regarding the use of anti-CGRP agents.
“These new therapies are highly effective in responders, allowing patients to diet, exercise and improve many cardiovascular lifestyle factors, without the risk of weight gain that we encounter in so many of our oral migraine preventive medications,” she said.
“So the potential findings need to be balanced with other factors too in individual management.”