Brain disease treatment shows promising signs

Early results for a potentially revolutionary brain disease therapy given under compassionate use to a two-year-old has shown promise, a University of Manchester scientist told an international conference on Wednesday 13 May.

Professor Brian Bigger who was presenting at the American Society of Gene & Cell Therapy 23rd Annual Meeting told delegates that the safety and feasibility of the investigational gene therapy for the rare and life-limiting Sanfilippo disease type A is now becoming more clear, as a formal clinical trial gets underway. The trial is funded by Orchard Therapeutics, who hold the license and commercial rights to the Sanfilippo disease type A programme.

The investigational gene therapy, which involves harvesting patient’s blood stem cells, was delivered by Professor Rob Wynn under a specials licence at The Royal Manchester Children’s Hospital (RMCH) in 2019. The therapy and trial follow over a decade of development and pre-clinical work by Prof Bigger at The University, together with clinical collaborators Prof Wynn, Prof Ed Wraith and Dr Simon Jones at Manchester University NHS Foundation Trust (MFT) and Prof Adrian Thrasher at Great Ormond Street Hospital.

The process is as follows:

  • A type of virus known as a lentiviral vector is used to deliver the patient’s missing ‘SGSH’ gene to the blood stem cells in the laboratory.

  • The manufactured gene-modified stem cell product is transplanted back into the patient.

  • The stem cells then regenerate the immune system providing the patient with the working – and potentially permanent – copy of the gene.

Sanfilippo disease type A, or MPSIIIA, causes a progressive loss of developmental skills in young children. They suffer deafness, hyperactivity and behavioural problems, progressive developmental delay, and seizures during the later stages of the condition. The condition is usually fatal in late childhood or early adulthood.

Professor Bigger said: “These results are promising and provide some hope for these children whose condition was previously thought to be incurable. The trial is the critical next stage, but it’s true to say we are excited.