Cape Town - For years, children suffering from tuberculosis have been relying on pungent, adult-size tablets.
The type that have to be halved, quartered or crushed in order to have the correct doses administered.
However, it is hoped that a study being conducted by Stellenbosch University and the UK Medical Research Council will result in pleasant-tasting medicines in the correct dosage being manufactured.
The Shine study, which is conducted in Cape Town, Uganda, Zambia and India, is putting paediatric TB patients on a child-friendly single dose combination drug which will also hopefully cut the treatment period from six months to four. About 1 200 children would form part of the study.
Current TB treatment involves six months of treatment – a two month intensive phase of three or four drugs, followed by a maintenance phase lasting four months. The doses prescribed for children are currently measured on a weight-based scaling-down of the adult medication, resulting in uncertainty over the exact paediatric dosage.
Professor Anneke Hesseling, director of the Desmond Tutu TB Centre at Stellenbosch University, said the latest clinical trial, which is scheduled to start in June, would use a new child-friendly formulation that combines all the TB drugs into a small, pleasant-tasting tablet that can be dissolved in water.
Hesseling said that World TB Day, commemorated on Thursday (March 24), should be used to create awareness about the challenges facing children with TB. She added that paediatric TB had been neglected for years, with little research done to advance treatment. Long treatment regimens, bitter-tasting adult sized tablets and painful injections with serious side effects were some of the challenges children with TB had to endure.
Hesseling said that if the 18-month trial is successful, it could be a “game changer”.
“If we manage to treat TB within four months we think that can also improve treatment adherence,” she said.
Despite these challenges, most children did well on treatment.
“We can cure children with TB, but the challenge is to make the treatment more friendly to children and families by making the regimen shorter and giving children medication that is easy to swallow.
“There are fewer actual TB organisms in a child with pulmonary TB and therefore fewer organisms to kill. So there is a real opportunity to shorten the treatment for drug-sensitive TB in children,” she said.
Meanwhile, a landmark study conducted in the Western Cape by UCT-based SA Tuberculosis Vaccine Initiative has reported the discovery of a blood test that can predict whether someone is likely to develop TB long before the disease manifests.
The research, which is being published in the Lancet, suggests that the newly discovered biomarker test would allow clinicians to identify three-quarters of those who will develop TB, ensuring early detection and benefit from health care. The “correlate of risk” blood test measures the gene expression signature.
Professor Willem Hanekom, principal investigator of the study, said the test could predict progression to TB more than one year before disease manifests, which provides a window of opportunity to use treatment to prevent the disease.
This 10-year discovery effort was led by scientists at Satvi and the Centre for Infectious Disease Research (CIDR) in Seattle, US. They studied gene expression patterns in blood samples selected from more than 6 000 teenagers from Worcester, who were followed for more than two years to identify those who developed TB.
Confirmation that the gene expression signature could predict TB disease was completed using samples from 4 500 adults from South Africa and Gambia.
The blood test would soon be evaluated in a clinical trial, funded by the Bill and Melinda Gates Foundation, to determine if targeted preventive therapy for people with a positive test could stop them from developing TB.
Professor Mark Hatherill, principal investigator of the new trial, said that if the trial was successful, mass campaigns using a “screen and treat” strategy could have a major impact on the global epidemic “by stopping TB before it manifests and becomes infectious to others”.