Even a year and a half ago, there was no effective treatment for SMA in Poland. Currently, more than 700 patients are receiving the first drug for this disease - nusinersen, under the program "Treatment of spinal muscular atrophy". Prof. dr hab. n. med. Anna Kostera-Pruszczyk.
Nusinersen is a drug that can protect the youngest patients from disability and even death. In adult patients, thanks to treatment, an improvement is also observed, and the lost functions return, which translates into their greater independence.
What is SMA? What is its face and why is the disease so dangerous? What has the decision of the Ministry of He alth on reimbursement of modern therapy changed in the lives of patients and their families? We talk about it with prof. dr hab. n. med. Anna Kostera-Pruszczyk, neurologist, head of the Department and Clinic of Neurology at the Medical University of Warsaw.
- SMA is a disease that for many years no one, apart from neurologists, has heard of. Please explain what it is.
Prof. Anna Kostera-Pruszczyk:Spinal muscular atrophy is a genetically determined disease. It is classified as a rare disease. It is inherited recessively, which means that a child usually inherits it from both parents. Parents are able-bodied people and usually do not expect that they will pass on the defective gene to their offspring.
Due to the method of inheritance, several children in one family may suffer from spinal muscular atrophy. But not all children get sick in the same way. The timing of symptoms and their severity may vary. Most often, SMA is diagnosed in childhood.
At the root of the disease there are mutations in the gene, which is abbreviated as SMN1. Every he althy person has the SMN1 gene and a similar but not identical SMN2 gene. The SMN1 gene is responsible for the production of a very important protein called the life protein of motor neurons.
Due to the nearly identical SMN2 gene, a protein is also produced, but there is less of it than due to the function of SMN1, and it is also less stable. In a he althy person, the amount of this protein does not matter, but in a person suffering from spinal muscular atrophy, the more protein produced by the SMN2 gene (the greaternumber of copies of SMN2), the milder the disease is usually.
- How is the disease going?
A.K-P.:In the most severe, but also the rarest cases, the disease may reveal itself already in the prenatal period. This is called SMA0. The most common form is early infancy, i.e. SMA1. The child seems he althy in the first few months of life, but does not develop any motor skills that are seen in he althy children. Without pharmacological treatment (which we have had for a year and a half), these children developed respiratory failure which was the cause of death.
Another form of the disease, i.e. SMA2, is slightly more chronic. Symptoms are observed in the second half of life, children sit but do not walk independently. Another form of SMA3 disease, in which the child sits on his own, starts to walk over time.
However, due to the progression of the disease, these skills are lost after a few or several years. SMA is a severe, progressive disease that always leads to severe disability.
- You mentioned that sometimes the disease is diagnosed in utero.
A.K-P.:It's true, but it's very rare. Early diagnosis is ideal from the point of view of the effectiveness of the therapy. We have excellent genetic tests that allow us to quickly identify spinal muscular atrophy.
Newborns are screened in the world and in several European countries in order to detect the disease as early as possible, in an asymptomatic period and to start treatment before irreversible damage occurs to the body. There is no newborn screening for SMA in Poland yet. The introduction of such a program would further increase the effectiveness of the therapy. In terms of content, we are prepared for it.
It may be worth emphasizing at this point that Poland is the European leader in neonatal screening, thanks to which we detect many dangerous diseases very early and implement effective treatment quickly.
- Medical statistics show that there are 850-900 people suffering from SMA in Poland. Does a similar scale of the phenomenon occur in Europe and in the world?
A.K-P.:Our epidemiological indicators do not differ from the global ones. The published studies show that each year in Poland about 50 children are born, diagnosed with spinal muscular atrophy. This group includes children who will develop SMA1 in the first months of life and patients with SMA2 and SMA3 who will develop symptoms later.
- Until January 2022patients with SMA could only be offered rehabilitation, dietary treatment. The situation changed dramatically after the introduction of reimbursement for a drug that effectively copes with the symptoms of the disease. Is it a medicine for all patients?
A.K-P.:Symptomatic treatment, i.e. rehabilitation, adequate diet, sometimes orthopedic treatment is still very important for patients. The drug that is available in Poland is a drug for all patients, regardless of their age.
The greatest effectiveness is obtained by administering the drug as early as possible, before the appearance of advanced symptoms of the disease. We currently have a year and a half of experience in running the NHF drug program in SMA.
Improvement, although less spectacular, is observed even in patients who have a severe and advanced form of the disease. These patients need more time to improve their fitness status, but there is progress. The youngest children respond best to treatment.
- This is a special moment not only for patients but also for neurologists.
A.K-P.:That's right. Thanks to the reimbursement and drug program, we have gained an effective weapon to fight this catastrophic genetically determined disease. Of course, it is not a drug that will completely cure our patients, but it prevents the disease from progressing and gives them a chance to avoid disability and, in the case of the youngest, to live a normal life. What's more, another hope is also born.
Gene therapy for children under 2 years of age has been registered in the USA. Perhaps, in the next few years, we will be able to reach for drugs that are more tailored to the patient's needs.
- How many patients in Poland benefit from modern treatment?
A.K-P.:Currently, this therapy is used by over 700 patients, both children and adults, Extending modern treatment to most patients with SMA also means that in less than a year since the launch of the drug program, we have been able to implement the theory into clinical practice.
- Patients who receive the drug see improvement, sometimes they are very surprised that they can do something that was impossible again.
A.K-P.:This is actually happening. We also notice it. The new therapy enables patients to do what they have not done in months or years. Or it happens that the patients do not lose their mobility. It is a great satisfaction for everyone. Regaining, even only partially, independence, especially in the case of chronic diseases, is a great breakthrough. A patient who was not independent, required 24-hour care, can eat and dress himselfmyself. SMA is a lifelong disease.
Usually our patients are looked after by their families. Improving the he alth of a son or daughter is also a great relief for parents, sometimes sick and advanced in age. They emphasize that watching the return to independence takes a huge burden off their shoulders. This has not only a medical dimension, but also a human one. The fact that you regain fitness also has a therapeutic dimension. The patient is more willing to exercise, and tries harder during rehabilitation.
In short, our pupils are ready to live again. I hear often from young people - I completed my bachelor's degree, now I'm enrolling in master's studies, because I know that I have enough strength to complete them. Someone who worked part-time decides to take up another challenge or devote more time to rehabilitation. In short, the quality of life of patients is changing dramatically.
- Once started, does the therapy have to be continued until the end of life?
A.K-P.:From what we know about the mechanism of the disease and the mechanism of action of the drug, we are dealing with a chronic treatment of a chronic disease. The treatment regimen is one for everyone, regardless of the severity of symptoms and the age of the patients. The rules of participation in drug programs are described in detail by the National He alth Fund.
Before starting treatment, three main conditions must be met. First, genetic testing must confirm the diagnosis of SMA. Second, it must be possible to administer the drug directly into the spinal canal because that is how the drug is administered. The third condition is the patient's consent to the treatment. In Poland, treatment is carried out in almost 30 departments of neurology and pediatric neurology.
I hope that all patients will be able to enter the drug program by the end of this year. Currently, newborns diagnosed with SMA are not awaiting treatment. In Rzeszów, at the Department of Pediatric Neurology, the team of doctor Elżbieta Czyżyk administered nusinersen on the second day of the child's life. It is a huge success. It also shows the determination with which we act if we can heal, we do it immediately.