Forward to the past for a better cure
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Forward to the past for a better cure

As part of our Female Leadership series, Life talks to the Medical Cannabis Research Team of Rangsit University, pioneers in developing marijuana-based medicine in Thailand

Forward to the past for a better cure
Asst Prof Dr Surang Leelawat in her medical lab at Rangsit University. Photos courtesy of Rangsit University

Though more and more countries have legalised marijuana for medical purposes, cannabis is still illegal in Thailand. But realising the gradually shifting tide, Rangsit University founded the Medical Cannabis Research Team last year in the hope of securing scientific proof on the medical benefits of cannabis -- and, pending a possible law change, to bring it back to Thai medicine for the first time in centuries.

Thailand's pioneers in cannabis study are three female pharmacists from the university's pharmacy faculty: Assoc Prof Dr Narisa Kamkaen, the team leader; Asst Prof Dr Surang Leelawat; and Dr Worawan Saingam.

Prominent among the three is Dr Surang, the first Thai academic pharmacist to conduct groundbreaking research on the use of marijuana extract to treat cholangiocarcinomas, or bile duct cancer.

It started in 2006, when she received a two-year grant from the Thailand Research Fund to study the effects of medical marijuana.

"A lot of medical research showed that marijuana extracts can stop or slow the growth of some cancers, but no one had studied the effects of marijuana extracts on cholangiocarcinomas," she said.

She is interested in bile duct cancer because it is a primary liver cancer -- a leading cause of death in Thailand, especially among men. The Northeast has the highest bile duct cancer, caused by a parasite, or a liver fluke, found in raw fish dishes. The disease is a silent killer because patients are usually not aware of the sickness until it is in the advanced stage. About 20,000 people die per year because of liver cancer.

"I thought if I could discover something [about the cure], I would be so proud," she recalled of her ambition.

The two-year research yielded an awe-inspiring result. With marijuana extracts supported by the laboratory of a public hospital, she found that the herbal compound could slow cancer-cell growth and stop its spreading to different parts of the body.

The result was verified and published in Cancer Investigation, a medical journal in the United States, in 2010. The full title of the research is "The Dual Effects Of 9-Tetrahydrocannabinol On Cholangiocarcinoma Cells: Anti-Invasion Activity At Low Concentration And Apoptosis Induction At High Concentration."

After the first finding, Dr Surang didn't have a chance to pursue her research until she picked it up again last year. One of the reasons is that marijuana is still classified as an illegal drug in Thailand -- this despite the fact that for centuries cannabis was part of Thai traditional medicine.

Part of the tradition

Right Assoc Prof Dr Narisa Kamkaen. Photo courtesy of Rangsit University

Use of the weed for medical purposes can be traced back to the period of King Narai the Great (1656-1688) of Ayutthaya Kingdom, according to the Institute of Thai Traditional Medicine Department Director Dr Kwanchai Visithanon.

"Cannabis was part of at least 91 formulas of Thai traditional medicine," he said, adding that it was used to improve food intake, promote sleep, relieve pain and anxiety, and treat epilepsy.

"The portion of weed used in each formula is small. It is also mixed with other herbal ingredients to reduce the side effects of marijuana," he said.

Cannabis itself has more than 400 chemical compounds, but there are two active components used for the medicinal approach: tetrahydrocannabinol (THC) and cannabidiol (CBD).

THC is responsible for the getting-high feeling, but can also ease pain and nausea, reduce inflammation and act as an antioxidant. CBD, on the other hand, can counteract the high caused by THC, and can also reduce anxiety, spasticity, pain and sleeplessness.

In some parts of the world, marijuana extracts have been used for treating patients with many types of symptoms, such as Alzheimer's disease, autism, cancer, chronic pain and multiple sclerosis, or MS.

Today marijuana is legal for medical purposes mainly in Europe, South America, Australia and Canada, as well as 29 of the United States, while a handful of countries have legalised its use for recreation. Some countries -- such as Chile, Colombia, Jamaica and Spain -- even allow cultivation of the weed.

However, in Thailand marijuana is categorised as a Class 5 narcotic under the 1979 Narcotic Drugs Act. The law prohibits production, consumption, sale, import, export or possession of the drug, unless permitted by the Public Health Minister on a case-by-case basis.

Dr Kwanchai said, however, that cannabis does not display any effects that fit into the definition of an addictive drug. The Narcotics Drugs Act defines the term "narcotic" as any form of chemicals or substances that when consumed, causes physiological and mental effects in a significant manner, such as a need to increase dosage, withdrawal symptoms when consumption ceases and permanent health deterioration such as brain damage.

"Marijuana does not have such effects. It is even less intoxicating than alcohol," the doctor said, believing there are no valid reasons to categorise marijuana as an addictive drug.

When the narcotics law was enacted in 1979, marijuana was removed as a traditional herbal medicine.

"Thailand should allow marijuana for medical use so that we can bring back our traditional formulas for the benefit of patients," he said.

Progress to legalise marijuana is slow, although the amendment of the Narcotics Drugs Act received public hearings and approval by the Office of the Council of State last year.

"The amendment will allow the use of marijuana for scientific research and for medical purposes," said Wicha Mahakhun, dean of the law faculty at Rangsit University and the ex-commissioner of the National Anti-Corruption Commission. "If there is no amendment, we can't conduct marijuana research that involves real patients, let alone treating sickness. The change is minor, but it will bring enormous benefit," he said.

The next step is to submit the amendment to the National Legislative Assembly of Thailand, but it's unclear when it will happen.

Medical marijuana

While the winds of change are beginning to blow, Rangsit University is determined to be a pioneer in medical marijuana research. Last year, the Medical Cannabis Research team asked for permission from the Public Health Minister to conduct three separate research studies: to produce marijuana extracts for research, to conduct an animal experiment on treating bile duct cancer cells with THC, and to produce a prototype of a mouth spray.

It is illegal to grow the plant, so the research team asked for 40kg of seized marijuana from the Narcotics Control Board. They also obtained permission from the Food and Drug Administration (FDA) to store the cannabis in a secure place, strictly for the use of research.

Dr Narisa Kamkaen was responsible for producing marijuana extracts. She successfully extracted THC and CBD from seized marijuana, although she found the seized weed was contaminated with mould and bacteria.

She hopes the research team will be able to grow the plant in a closed growing environment in order to produce organic marijuana.

Dr Surang Leelawat is continuing her experiment on the effects of THC on bile duct cancer cells. Since last year, she has studied the treatment with rats.

The process started with the administration of bile duct cancer cells to rats and then injecting the marijuana extract to find out if the compound can slow the growth or reduce the size of cancer cells in the animal. Results of the lab tests can be used for calculating dosage for future patients, she said.

Dr Surang expects to complete the experiment within the next four months. She also hopes to have a chance to conduct clinical trials after the animal experimentation in order to test the effectiveness, safety and side effects of marijuana in the short and long term.

Dr Worawan Saingam is in charge of formulation development of oromucosal spray from cannabis extract. She applies the approved formula of FDA, which is used in licensed cannabis-based medicine in developed countries like the United Kingdom. It indicates that each 100 microlitre spray contains 2.7mg of THC and 2.5mg of CBD.

The formula is used for the treatment of spasticity due to multiple sclerosis (MS) and cancer-related pain, and for reducing nausea and vomiting in cancer patients who have received chemotherapy. The mouth spray was introduced to the public at the beginning of this month.

"Oromucosal spray is ready to use, but we can't run the test with real patients yet," she said.

The research yielded fruitful results in the lab tests. Unfortunately, it is still illegal to conduct clinical trials or produce marijuana-based medicines to treat patients in Thailand.

"The success of our Medical Cannabis Research team is remarkable. It is the first scientific proof discovered by Thais. We all should be proud," said Rangsit University President Dr Arthit Ourairat.

The accomplishment in the laboratory should be further developed in clinical studies, he said, adding that it is important to amend the Narcotic Drugs Act to allow patients to use marijuana for medical purposes.

It is a controversial issue that needs the courage of a leader.

"If the prime minister invokes Section 44 to amend the law, it will bring huge benefits not only to patients, but to the development of Thai traditional medicine in the future," he noted.

A prototype of the marijuana-based spray. Photo

Dr Worawan Saingam, who's developing a prototype of the oromucosal spray. Photo courtesy of Rangsit University

The Medical Cannabis Research Team of Rangsit University received 40kg of marijuana at the Office of the Narcotics Control Board last June. Photo courtesy of Rangsit University

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