Source: NATIONAL UNIVERSITY CANCER INSTITUTE
GASTRIC cancer patients may need just a few jabs to suppress their cancer – rather than go through arduous chemotherapy treatment – if a new cancer vaccine proves to be effective.
The vaccine, believed to be the first to target gastric cancer, is now being tested at the National University Hospital. It was developed by Japanese biomedical firm OncoTherapy Science.
The clinical trial, which is being carried out at the hospital’s National University Cancer Institute seeks to test the vaccine on 30 patients over the next two years, said lead investigator Yong Wei Peng at a media briefing yesterday. They must be advanced gastric cancer patients who have failed to respond to or are unsuitable for standard therapy. They must also carry a specific protein that is present in one-third of Singaporeans. This is because the vaccine currently works for this group of people only, said Dr Yong, who is an oncologist at the institute.
So far, one patient has been recruited. Typically, a drug has to go through three phases of testing before it can enter the market.
Gastric cancer is the sixth most common cancer in Singaporean men, and ninth in women. Every year, about 330 people here die from it. It is particularly common in Chinese men. But less than half of advanced gastric
cancer patients respond well to chemotherapy – meaning that their tumour shrinks by 30 per cent or more, said Dr Yong. Many are often too weak to withstand chemotherapy as their cancer is discovered late. “It is important for us to develop a new treatment that is more tolerable to standard therapy,” he said.
The new vaccine shrinks cancer tumours by rallying the immune system to recognise and attack cancer cells. This is done by injecting a combination of five different proteins under the skin, near the lymph nodes where white blood cells are produced.
For this trial, one jab containing 1mg of the vaccine will be given every month. It is unclear whether the vaccine can actually cure the cancer. Such therapeutic cancer vaccines seek to kill cancer cells directly. The current
vaccine for cervical cancer, in contrast, prevents, not kills, the cancer. Such a vaccine, if found to be successful, has the potential to replace chemotherapy, said Dr Takuya Tsunoda, president and chief executive of OncoTherapy Science.
He added that the cost is likely to be half that of chemotherapy, which can range from $500 to $5,000 a month here. One cycle of chemotherapy typically lasts for six months. But other oncologists warn against the idea that this may be a “miracle cure”.
Dr Wong Seng Weng, medical director of The Cancer Centre at Paragon Medical, said: “Therapeutic cancer vaccines have been studied for close to a decade, and... there have been many failures along the way.”
But he added: “Whether this will also fail like the others, I don’t know. But even if this vaccine is shown to extend
the patients’ lives by a couple of months, it will be considered a success.”