The European Medicines Agency is recommending that the world's leading malaria vaccine be licensed even though it is only about 30 percent effective and that protection fades over time.

In a statement published on Friday, the agency said it had "adopted a positive scientific opinion" for the vaccine's use outside the European Union, a regulatory process that helps speed new medicines to the market.

The vaccine, known as Mosquirix and made by GlaxoSmithKline, protects only about one-third of children though it might help protect some kids from getting the parasitic disease.

"This is not the big game changer that we were hoping for," said Dr. Martin De Smet, a malaria expert at Doctors Without Borders. "The vaccine itself remains disappointing but this is an important step forward," he said, noting the World Health Organization would be issuing its recommendations on how the vaccine should be used in November.

WHO had previously set a target of 2015 for having a malaria vaccine that was at least 50 percent effective with protection lasting longer than one year.

Even though that goal has been missed, De Smet said the vaccine isn't a waste since it could help reduce the huge burden of malaria: there are about 200 million cases and more than 500,000 deaths every year, mostly in African children.

"In countries where children get four to six episodes of malaria a year, this will make a big difference," he said, adding that people shouldn't stop using other prevention tools like bed nets and insecticides.

De Smet was unsure whether the vaccine would ultimately prove to be cost-effective and suggested countries with year-round malaria cases would benefit the most.

"We cannot afford to not make use of an additional tool, even if (it is) highly imperfect," he said.