TB vaccine trials in fourth month

Tuesday November 25 2008

By GATONYE GATHURA

Clinical trials of a new TB vaccine enter their fourth month next week in Kombewa near Kisumu amid fears that funding gaps may worsen with the deepening global cash crisis.

In the first stage of human testing, known as Phase I trials, the new vaccine is being tested for safety on adults with no previous history of TB at the Walter Reed Project in Kombewa.

The Walter Reed Project is the medical research arm of the US military, and has been working with the Kenya Medical Research Institute (Kemri) on several programmes.

Researchers hope the candidate vaccine will improve immunity in people who have already received the standard Bacille Calmette Guérin (BCG) vaccine.

Although most Kenyans were vaccinated with BCG, the vaccine is said to be no longer as effective as it once was.  

BCG is usually administered to newborns, but in HIV-positive people, it can cause serious and even fatal diseases if HIV weakens the immune system, allowing the vaccine to multiply unchecked. 

“I am glad that a high burden country like Kenya has been selected in these broader efforts in advancing new tools required in global TB control efforts, more so in an era where TB-HIV co-infection is a great challenge,” said Ms Lucy Chesire, who is a tuberculosis advocate and survivor.

A similar study is going on in South Africa where screening of volunteers has been done and actual immunisation is going on.

The vaccine will be tested on 82 adults who have had active TB.

Previous studies

The trials began just days after a co-discoverer of HIV and recent Nobel Prize winner, Françoise Barré-Sinousi, said that the global financial crisis could lead to further funding shortfalls in the fight against TB.

The vaccine candidate, Aeras-402/Crucell Ad35, has been jointly developed by Dutch company Crucell and Aeras Global TB Vaccine Foundation.

The foundation’s director of communications, Annmarie Leadman said previous studies on the vaccine in the US have shown encouraging results.

Kenya is ranked 10th among the 22 countries which account for 80 per cent of the world’s TB cases. Locally, the disease causes an estimated 74,000 deaths each year, translating to 200 deaths a day.