A Russian billionaire has donated GBP 1.1 million to pay for the world’s most expensive medicine for a two-year-old boy with a rare disease.

Alisher Usmanov, the top shareholder of copper production company Udokanskaya Med, donated RUB 115 million (GBP 1.12 million) to fund the treatment of young Kostya Gepalov, who suffers from type 1 spinal muscular atrophy (SMA).

Kostya’s parents were overjoyed with the donation and were able to close the online fundraiser they had started for him in the hope of paying for his pricey treatment.

In a message posted to Instagram on 31st May, the couple wrote: “We’ve gone lengths to get here. And it’s finally happened. A kind man has given Kostya 115 million rubles.

“Alisher Burkhanovich Usmanov, the top shareholder of Udokanskaya Med, became our magician, the person we have been looking for and waiting for for so long, who came to help his little fellow countryman, Kostya.”

Kostya suffers from the most severe form of SMA, and the authorities of Zabaykalsky Krai, where the family lives, had refused to purchase Zolgensma, a gene therapy medicine, for his treatment, as the cost was too high.

Svetlana Gepalova and her husband started an online fundraiser and had managed to raise an impressive RUB 53 million (GBP 513,799) before Usmanov’s generous donation, which took them to their target.

Zolgensma has been cited as the most expensive medicine in the world, costing at least USD 2.1 million (GBP 1.5 million) for a single treatment.

It is administered just once, and Kostya would be denied it under European rules, as he turned two years old in September last year.

However, under American rules, which go by weight rather than age, he is still eligible to receive the treatment, which the family hopes he can receive in Moscow.

Type 1 SMA sufferers gradually lose most of their muscle function, with death usually caused by the failure of the respiratory muscles. Sufferers do not generally survive past the age of two.