SINGAPORE: A kind of cell therapy for cancer is approved for use in Singapore and offers another treatment option for patients with certain types of advanced blood cancers who are not in remission despite having undergone other forms of treatment.
Such patients include children with acute lymphocytic leukemia – the most common childhood blood cancer in Singapore – if they meet certain criteria.
The new treatment works by removing disease-fighting cells called T cells from patients, genetically manipulating them to attack cancer, and putting the cells back into it.
Developed by the Swiss pharmaceutical company Novartis, the therapy is called CAR-T, or chimeric antigen receptor T cell. It is marketed commercially as Kymriah.
It was approved under Singapore’s new regulatory framework for cell, tissue and gene therapy products (CTGTP), which took effect on March 1.
Singapore is the first country in Southeast Asia to offer the treatment.
Professor William Hwang, Medical Director of the National Cancer Center Singapore, explained how the therapy works: “Imagine cancer cells as criminals and T cells as police officers. When there are strong, persistent and covert criminals in the city that the police officers cannot get rid of, the CAR-T process is like taking out the police officers, giving them training to recognize all the criminals and bringing them back to the city to enemies. “
Prof Hwang described it as a “breakthrough”.
“It is a significant advance in the emergence of immune-based treatment strategies and is an important step forward in providing life-saving, individualized cancer treatments for blood cancers and conditions,” he said.
However, treatment is expensive and there are potentially serious side effects.
WHO IS ELIGIBLE?
The therapy is approved for children and young adults with advanced blood cancers, especially patients aged 2 to 25 years B-cell acute lymphoblastic leukemia (ALL) that is resistant and has relapsed after or after transplantation.
Acute lymphoblastic leukemia causes most patients to become anemic and prone to infection. Signs and symptoms include being prone to bruising easily or bleeding from small wounds for a long time.
Adults with diffuse large B-cell lymphoma (DLBCL) that is resistant or has relapsed after two or more lines of systemic therapy may also be eligible for the therapy.
Singapore General Hospital (SGH) is Kymriah’s first treatment center to become operational in Southeast Asia, Novartis said. The National University Hospital (NUH) is making the necessary preparations to become a qualified Kymriah treatment center.
At SingHealth, to which SGH belongs, there are a “number of patients” who have received the therapy as part of clinical trials, said Dr. Hwang, who is also head of the SingHealth Duke-NUS Cell Therapy Center and senior consultant for hematology at SGH. .
Because the therapy was only recently approved, fewer than 10 patients have undergone the therapy outside of the trial and are being monitored, he added.
“All patients who have received CAR T therapy for lymphoma in SGH have responded very well to the therapy and are being monitored,” he said.
Doctors said the treatment opens up options for patients who do not qualify or who do not meet current standards of care and who are otherwise likely to die from the disease due to the lack of alternative treatment options.
For patients with B-cell ALL who have relapsed or resistant cancer, less than 10 percent of patients survive five years, said Dr. Allan Yeoh, chief of pediatric hematology and oncology at Khoo Teck Puat-National University Children’s Medical Institute at NUH.
With the new treatment, several studies have shown “significantly improved patient outcomes with lasting responses,” he added.
“This gives hope to eligible patients, including pediatric patients, in Singapore and the region who are looking for a different way to treat their cancer because previous treatments have not kept their cancer in remission,” said Dr. Yeoh.
During processing, the modified T cells are grown, washed, formulated and frozen before being returned for infusion. (Photo: Novartis)
Dr. Hsieh Wen Son, a medical oncologist at the Icon Cancer Center, said the availability of Kymriah provides “much-needed” therapy for patients who have no other therapeutic options.
“In addition, it opens the door in terms of the infrastructure and expertise for these and other new cellular therapies to treat a variety of cancers,” he said.
POSSIBLE SIDE EFFECTS AND MANAGEMENT
While the therapy can be lifesaving, it has potentially serious side effects.
A common side effect is cytokine release syndrome, which also indicates that cancer cells are being eliminated, the doctors said. The syndrome also means that the CAR T cells are working and eliminating the cancer cells.
Symptoms include a high fever and low blood pressure in the days after treatment is given.
Other side effects include changes in the brain that cause swelling, confusion, seizures, or severe headaches.
However, doctors said the side effects can be managed effectively by a trained clinical care team.
As with chemotherapy, CAR T cells can kill some of the good B cells that help fight infections, so the patient undergoing treatment may be at a higher risk of infection, said Dr. Hwang, adding that this can be managed .
“Since the patient undergoing treatment would be closely monitored by a clinical care team, these side effects would be managed and symptomatic treatment would be administered,” he said.
More severe symptoms can temporarily affect speech or cause hallucinations or seizures.
“In most cases, symptoms appear within eight weeks of receiving therapy and resolve within 12 days,” said Dr. Yeoh.
According to the Health Sciences Authority’s Patient Education Package Insert on Therapy, “very common” side effects that may affect more than one in 10 people include heart, lung, kidney failure, and liver damage, usually within 10 days of treatment. .
Other possible side effects include feeling hot, fever, chills, chills, sore throat or mouth ulcers, which could be signs of an infection.
“Some infections can be life-threatening or fatal,” said the package insert.
POSSIBLE BARRIERS TO TREATMENT
Dr. Hsieh and Dr. Colin Phipps Diong, a senior consultant in hematology at the Parkway Cancer Center, said the high cost of the treatment would pose a significant barrier to patients.
While Novartis has not said how much the one-time treatment will cost in Singapore, it will cost up to US $ 475,000 (S $ 635,170) in the United States.
Dr. Hwang said the cost “depends on the overall treatment the patient receives for his condition.”
“Patients may be eligible for financial assistance from various government grants and from various charities at SingHealth institutions, such as the NCCS Cancer Fund, which provides financial assistance to patients in need,” he said.
Likewise, Dr. Yeoh said, “We recognize that cancer treatment can be a heavy financial burden, and that patients in need may qualify for financial assistance under various government support schemes.”
He added that there is also the NCIS Cancer Fund that provides for patients in need who may need additional support.
Dr. Hsieh also said the “significant side effects” that can occur in some patients may be a limiting factor.
“A careful risk / benefit assessment must be applied to each patient,” added Dr. Diong admits.
“Patients with highly active ALL or DLBCL are highly likely to fail CAR-T therapy, while at the same time being at high risk of serious complications with treatment,” he said.