Cuba has a possible lung cancer vaccine that America can now test

The United States and Cuba have taken major steps to end their 50 years of hostility, and some researchers think Americans could reap an unexpected benefit: better access to Cuban medical innovations.

"The US may be the world leader in basic cancer research, biotechnology, and treatment," explained Marga Gual Soler, who studies science diplomacy. "But Cuba has built a universal, free, and public health care system, [and] has the highest number of medical doctors per capita in the world, a robust biotechnology industry developed with very low resources, and guaranteed access to drugs and advanced diagnostics for the population."

Havana, Cuba. (ADALBERTO ROQUE/AFP/Getty)

One of the first diplomatic exchanges involved Cimavax, a lung cancer vaccine first developed in Cuba. But it doesn't work for prevention like a traditional vaccine; instead, it stimulates the immune system in a different way, to stop cancers from growing in people who already have the disease. Researchers down there found that the vaccine increased survival rates and had few side effects in patients with late-stage disease.

There's reason to be cautious: US studies will need to replicate these findings in order to meet federal regulatory standards. And it's still a long way from clinical trials to being widely available for patients.

For now, scientists are excited about the possibility — and the exchange raises questions about how a political shift might spur medical innovation.

To learn more, I spoke to Dr. Kelvin Lee of Buffalo's Roswell Park Cancer Institute. Lee helped lead America's collaboration with Havana's Center of Molecular Immunology, which discovered the vaccine. Here, he explains why he thinks Cimavax is particularly promising, and why he's so enthusiastic about more Cuba-US medical exchanges.

Julia Belluz: How did your exchanges with the Cubans change how you think about medical innovation coming out of there?

Kelvin Lee: Everybody believes Cuba is this country stuck in the 1950s without realizing that the reason Cuban biotech is so innovative is because Cuba as a country has put a very high priority on health care. The public health care metrics are comparable to the US in terms of longevity and infant mortality. Cuba punches way above its weight. Because it is economically constrained, it has to be extraordinarily innovative.

They have two other anti-cancer vaccines [in addition to Cimavax] that are equally exciting but earlier in development. They also have a monoclonal antibody called Nimotuzumab [to treat brain cancer]. The US has monoclonal antibodies that target colon and lung cancers. However, those antibodies cause a fair amount of toxicity. Nimotuzumab does not have those side effects, so it's applicable for pediatric patients. They’ve used it in pediatric brain cancer. We don't have anything we can give to kids safely. That’s another drug we’d be very interested in seeing.

JB: So how did the warming of relations between the US and Cuba impact bringing Cimavax here?

KL: We got the license to import it, but what we needed were manufacturing documents from the Center for Molecular Immunology that described how the vaccine was manufactured, what quality control measures were taken, etc. This is 1,000 pages the FDA needs to review.

A trade mission [last year] allowed us to go down there and sign the agreements to move the documents forward. So the mission finalized the last piece and allowed us to march into clinical trials. This was one of the biggest obstacles for us. Many people think what Cuba has to offer the US is rum, cigars, and baseball players. Through the trade mission, many realized the biotech sector in Cuba is really remarkable.

JB: This vaccine is being called a revolutionary lung cancer vaccine. But it's actually more a treatment than what we typically think of as a vaccine. Can you explain exactly what Cimavax does?

KL: This vaccine has been developed by the Center for Molecular Immunology in Havana. They've been developing it since the late 1990s and have done a lot of interesting clinical trials, including a large phase 3 randomized controlled trial in 405 patients in Cuba. The patients had advanced-stage lung cancer, primarily because that’s their No. 1 cancer burden in Cuba and they don't have anything else other than first-line chemotherapy. Now it has been approved by the Cuban FDA for the treatment of lung cancer.

The vaccine is made out of a man-made protein that is called epidermal growth factor. This is a protein your body normally produces, and it helps support the growth of normal cells like skin cells. [It can also help cancer cells grow.] In those cells that become cancerous, this vaccine initiates an immune response against the epidermal growth factor protein, thus depleting an important thing the cancer needs to grow and survive. So the cancer can’t grow anymore.

JB: Could this method be applied to vaccines for other types of cancers or used for cancer prevention?

KL: Our Cuban colleagues have not tested that, because they’re economically constrained. They've only tested it in the No. 1 cancer burden in Cuba, lung cancer, and they haven't had the resources to do clinical trials in other types of cancer. [We'll study that.]

Can it be used in prevention? We already know patients that have early-stage lung cancer can get their cancers removed. We also know many are smokers who have damaged their lungs all over the place and have pre-cancerous lesions all over their lungs. They have a very high risk of relapse with a second lung cancer. We think the real potential for this vaccine is we can reduce the risk of relapse in this patient population.

One can think even further: If we develop an algorithm to predict a person's lung cancer risk, we could potentially vaccinate the very highest-risk cohorts to try to reduce their risk of lung cancer. That patient population is potentially in the millions, especially if you go worldwide.

JB: How far are we away from this vaccine reaching the US?

KL: Cuba has done the phase-three studies [the final preapproval phase studies to confirm safety and effectiveness], and there are other phase 3 studies going on internationally in lung cancer. But there has been no experience in the US because of embargo issues.

So we are predicting that the FDA is going to ask for a phase 1 study [which will test the drug in healthy people to confirm it's safe] in the US, just to replicate the safety data that our Cuban colleagues already reported. Once we get through that, we anticipate we won't see very much toxicity or anything different from what’s been reported. After that phase 1 study, we'll move on to other phase 1 studies in prevention and potentially in other cancers.

We will be filing an investigational drug application with the FDA. Hopefully we can get that document together and submitted this spring.

On a parallel track, we have two clinical trials that are in the institutional approval process here at Roswell Park. We are hoping to get those approved within the same time frame. That would mean we have trials here opening at the end of this year.