The breakthrough treatment is administered to those already suffering from the cancer, which kills 1 in 4 people in the island nation.
Cimavax has been shown to extend the lifespans of patients with lung cancer, which is known for killing sufferers quickly.
After being approved in Cuba - who have a first class health system despite being relatively poor - other countries around the globe are clamouring to get their hands on the vaccine.
But Cancer research warned that the test group in Cuba was very small (at 12), so firm conclusions could not be drawn just yet.
‘There were 12 people under 60 who had a good immune response and their improvement in survival was greatest - they lived on average for just over 15 months compared to 7.4 months for people who didn’t have the vaccine.’
Still, this is an exciting development in the fight against lung cancer - one of the most common and deadliest forms of the disease.