by Seth Augenstein, Digital Reporter
President Barack Obama’s visit to Cuba this month will be the first by an American president in nearly a century. The thawing relations between the two countries are expected to bring a bumper crop of famed Cuban among other imports.
Strangely enough, another eagerly anticipated product is a lung cancer vaccine some say could be a breakthrough in oncology.
CimaVax has reportedly been in development in Cuba for 25 years, partly because lung cancer is one of the leading causes of death in the Caribbean nation.
Health reporter, Maria Dorfner spoke with Dr. Kelvin Lee from Roswell Park Cancer Institute, located in Buffalo, New York. He says Roswell Park is finalizing an application to the FDA seeking permission to conduct a U.S. clinical trial of the cancer vaccine and that , depending on the results from that and any subsequent studies, it would likely be 5 or more years before the drug could be widely available for patients in the U.S. CimaVax is already an approved cancer therapy in Cuba and Peru.
HOW IT WORKS
The injection is not like the other cancer-fighting immunotherapies being developed in hundreds of American labs, said Kelvin Lee, the chair of immunology at the Roswell Park Cancer Institute in Buffalo, N.Y.
Lee and other doctors have visited the island nation several times to meet with its Cuban developers and hear updates on their progress –and they found that the vaccine was a promising potential breakthrough. He wrote in a post on Roswell Park’s Cancer Talk blog:
“Unlike other immunotherapies, CimaVax does not target cancer directly and it is not personalized. Rather, the vaccine targets a growth factor (EGF) necessary for the cancer to survive,” Lee said. “By targeting and effectively depleting this growth factor, the cancer starves and its progress slows, prolonging patients’ lives.”
The results so far show that patients’ lives were extended from six to an average of 18 months with the vaccine treatment, but there are reports of patients treated with the vaccine living five years or more.
Lee and the other doctors see the possibility that the vaccine’s efficacy may translate to colon, head and neck, prostrate, breast and pancreatic cancers as well, and that CimaVax may prove effective in preventing some cancers from developing or recurring.
Some studies have shown promise in CimaVax, as it has cut back the EGF needed for the cancer to progress.
It has done this with minimal side effects, including nausea, fever and vomiting. Survival dramatically improved in those patients with advanced Stage 3 and Stage 4 tumors, according to a Cuban study conducted in 2007.
However, the vaccine has only been administered to a few thousand people worldwide –and it is still far from FDA approval, the doctor said.
A possibility of skipping Phase I testing exists, Lee added. The FDA inspection period should end sometime this year, allowing testing to begin. Lee and the other doctors envision the vaccine’s efficacy translating over to other head and neck cancers, as well.
Cancer Research UK urged patience in looking to CimaCax, in a statement released last year.
“This research is promising but this is a small trial and we will need more trial results before we know exactly how well the vaccine works for people with lung cancer. A phase 3 trial is currently in progress in Cuba,” they said in a statement.
Obama announced the U.S. was “extending a hand of friendship” to Cuba – just 90 miles from Florida – in December 2014. The cooperation between Cuban and American doctors began in 2011 and gained momentum with New York Governor Andrew Cuomo’s trade mission to Cuba in April 2015. Since then, the U.S. has restored up to 110 daily flights to Havana.
Among the critics of Obama’s March 21 visit to the island nations are Sens. Marco Rubio and Ted Cruz, both presidential hopefuls who are of Cuban descent.
Scientists ‘find cancer’s Achilles heel’
Image copyright SPL
Scientists believe they have discovered a way to “steer” the immune system to kill cancers.
Researchers at University College, London have developed a way of finding unique markings within a tumour – its “Achilles heel” – allowing the body to target the disease.
But the personalised method, reported in Science journal, would be expensive and has not yet been tried in patients.
Experts said the idea made sense but could be more complicated in reality.
However, the researchers, whose work was funded by Cancer Research UK, believe their discovery could form the backbone of new treatments and hope to test it in patients within two years.
They believe by analysing the DNA, they’ll be able to develop bespoke treatment.
People have tried to steer the immune system to kill tumours before, but cancer vaccines have largely flopped.
One explanation is that they are training the body’s own defences to go after the wrong target.
The problem is cancers are not made up of identical cells – they are a heavily mutated, genetic mess and samples at different sites within a tumour can look and behave very differently.
They grow a bit like a tree with core “trunk” mutations, but then mutations that branch off in all directions. It is known as cancer heterogeneity.
The international study developed a way of discovering the “trunk” mutations that change antigens – the proteins that stick out from the surface of cancer cells.
Professor Charles Swanton, from the UCL Cancer Institute, added: “This is exciting. Now we can prioritise and target tumour antigens that are present in every cell – the Achilles heel of these highly complex cancers.
“This is really fascinating and takes personalised medicine to its absolute limit, where each patient would have a unique, bespoke treatment.”
There are two approaches being suggested for targeting the trunk mutations.
The first is to develop cancer vaccines for each patient that train the immune system to spot them.
The second is to “fish” for immune cells that already target those mutations and swell their numbers in the lab, and then put them back into the body.
Dr Marco Gerlinger, from the Institute of Cancer Research, said: “This is a very important step and makes us think about heterogeneity as a problem and why this gives cancer this big advantage.
“Targeting trunk mutations makes sense from many points of view, but it is early days and whether it’s that simple, I’m not entirely sure.
“Many cancers are not standing still but they keep evolving constantly. These are moving targets which makes it difficult to get them under control.
“Cancers that can change and evolve could lose the initial antigen or maybe come up with smokescreens of other good antigens so that the immune system gets confused.”
James Gallagher, health editor, BBC News website
Harnessing the power of the immune system – what’s known as immunotherapy – is the most exciting field in cancer and probably in all of medicine right now.
But while that excitement is justified, claims that a cure for cancer is around the corner are not.
Medical research is littered with the graves of hyped treatments that just never worked.
Two decades ago, gene therapy was “hype-central” and we’re still waiting for it to transform medicine.
This study demonstrates some spectacular science that furthers understanding of how the immune system and cancer interact.
But this new knowledge has not been used to treat a single patient. There have not even been animal studies. So there is a real risk it will not work.
Even if it does, this is an hugely expensive approach that would need to be customised to every patient in a process that takes more than a year from start to finish.
Some immunotherapy treatments work spectacularly with some patients’ cancer disappearing entirely.
They take the brakes off the immune system, freeing it up to fight cancer.
The researchers hope the combination of removing the immune system’s brakes and then taking over the steering wheel, will save lives.
Professor Peter Johnson, from Cancer Research UK, said the research had shown “impressive results in the clinic” and although “the technology is complicated and quite recent… once you start doing it the cost will come down”.
Dr Stefan Symeonides, clinician scientist in experimental cancer medicine at the University of Edinburgh, said designing a personalised vaccine was currently impractical, especially when a patient needed treatment straight away.
But he added that the “very elegant” study did provide a ground-breaking insight into current immunotherapy drugs, which do not yet work for most people.
“It’s not just the number of antigens, it’s how many of the cancer cells have them,” he said.
“This data will be quoted in discussions for years, as we try to understand which patients benefit from immunotherapy drugs, which ones don’t, and why, so we can improve those therapies.”
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