There is no cure for migraines, and most preventive treatments take quite a while to become effective. Because migraines can be debilitating and draining, researchers have been working on developing a medicine that could prevent another migraine within a few days, halting it before it appears. Now, researchers at Teva Pharmaceuticals in Frazer, Penn. believe they’ve developed an injectable drug that works within days, greatly decreasing the amount of time it takes for migraine treatment to work. The researchers published their findings in the journal Neurology.

In the study, the researchers examined 261 participants who had experienced migraines for an average of 18 years before starting the treatment. Over the course of one month, they had up to 162 hours of headaches — spread over the course of 22 days of headaches. For such people, migraines can take away from a normal, healthy life. The drug in question, known as TEV-48125, works as an antibody that blocks a certain peptide related to migraine pain.

Over the course of three months, 87 participants received a low-dose monthly injection, and 89 had a placebo shot. Another 85 had a high-dose shot. They were all given an electronic diary in which they recorded their migraines. It turned out that after just one week, the average number of migraine hours was reduced by 2.9 hours for those taking the placebo, while people taking the low-dose drug saw a 9.1 hour decrease in their average hours of pain. People who took the high- dose drug, meanwhile, saw up to 11.4 fewer hours of headaches. High doses of the drug started to work within a few days of participants taking it.

“Chronic migraine affects about 1 percent of all adults, yet less than 5 percent of those people receive a correct diagnosis and appropriate treatment,” said Dr. Marcelo Bigal of Teva Pharmaceuticals, an author of the study, in a press release. “Most people who receive preventive medication for chronic migraine stop using them, and one reason for that is the drugs can take a long time to become effective.”

People who qualify for preventive meds generally must experience over four migraine attacks per month, or if migraines last over 12 hours. Patients may also consider preventive drugs if their regular pain-relieving pills don’t seem to work. Typical preventive drugs include certain heart medications like beta blockers — which are normally used to treat high blood pressure or coronary artery disease — as well as antidepressants, interestingly. Some antidepressants have been found to reduce migraines. Others may include anti-seizure drugs and Botox.

The researchers of the latest study will need to do further research before the drug can be used clinically. “If these results can be confirmed with larger studies, this could be exciting for people with migraine,” Bigal said in the press release.

Source: Bigal M, et al. Neurology, 2016.