No meta-analysis in SMA treatment: Turkish doctor

By Faruk Zorlu

ANKARA (AA) - There have been no meta-analysis in spinal muscular atrophy (SMA) treatments, which has led to a significant disability that is rather new to yield concrete results, a Turkish pediatrician told Anadolu Agency.

"It is early to have a concrete conclusion. Actually, there may never be a conclusion or it may take a couple of years more to have an idea. However, all these treatment modalities (they are all molecular with different configurations) seem to be working," Haluk Aydin Topaloglu from Yeditepe University Department of Pediatrics in Istanbul told the Turkish news agency in an email interview.

There are three ongoing studies, including Nusinersen, gene therapy (Zolgensma), and Risdiplam, said Topaloglu. "So far, about 10,000 patients have received this molecule worldwide, while in Turkey, at least 650 patients are under current treatment with Nusinersen."

The first drug to treat SMA, Nusinersen, which was approved by the US Food and Drug Administration (FDA) in 2016, is widely used in almost all developed countries and larger data is being accumulated.

Another method is gene therapy, Zolgensma, which is currently conducted in several European countries along with Japan, Australia and the US, he added.

"Risdiplam study, which is under search and development, is also similarly active and widespread, including Turkey. There are two Turkish children that I personally follow at my institute in Istanbul," he said.

The efficacy of experimental drugs and treatments for SMA has not yet been fully proven.

- SMA studies with patients

Touching on SMA studies with patients, the pediatrician said studies are done in a limited number of cases. That also applies to other rare genetic disorders.

"I do not think there will be augmentation in the number of babies recruited because initial studies are always done on selected patients and age groups only to match with the demands of the statisticians to keep the data influx minimum required," said Topaloglu.

All SMA studies are carried out independently, but usually, drug companies are sponsors for clinical trials. These are joint-ventures of universities and the pharma industry, he said.

He stressed that clinical trials may not represent a real-world experience.

"I can give an example of the COVID-19 vaccines. Study cases were limited but now they have received worldwide appreciation.

"What we know for SMA is that all the time patients in the study arm have significantly better results than the placebo groups. This is a positive observation, and has led health authorities globally for approval," he said.

Commenting on the process of the development of the drug, he said first, developing the candidate molecule takes around 15 years. This is followed by a combined effort to test in clinical trials the form of phase I, II, and III in a cumulative manner. All these are preceded by animal studies before any use or trial in humans.

- Unaffordable SMA drugs

No family can afford to buy the drugs, except a few of the richest, he underlined. "So, all the financial burden is on health care providers, i.e. governments or wherever applicable, insurances."

The cost of partial treatments approved by health authorities in the US and Europe is much higher than the average family income. It could also be a huge economic burden to national health systems.

"We are talking about millions of dollars. Gene therapy for SMA (Zolgensma) is the single most expensive means of treatment for the time being," he said.

- Recommendations for families with SMA patients

On recommendations for families with SMA patients, he said the most essential issue in the treatments is that they should be initiated as early as possible, such as before 3 months old in SMA I --severe type. Otherwise benefit will probably be limited.

"All the treatment modalities at hand should be considered as disease-modifying agents, he said, adding that at an ordinary level, the efficacy of the drug differs among patients.

"The general health of the child such as nutrition, bone health, pulmonary, cardiac, etc should be monitored accordingly," he said.

He went on to say that all vaccination programs must not be neglected "To me, from a pediatrician’s point of view, SMA babies are not different than their peers."

- Situation in Turkey

According to the health ministry, an SMA case is found in every 6,000 births in Turkey.

Turkey has a policy of providing all approved treatments free of charge as Health Minister Fahrettin Koca announced on Jan. 3.

Families in Turkey launched a fundraising campaign on social media for the implementation of US gene therapy for their children. But NGOs have highlighted the inconvenience of such campaigns.

They contend that the effectiveness of drugs is not yet known so campaigns should not turn to the promotion of any experimental drug, and individual initiatives do not contribute to a collective solution.