A Novel Treatment for a Serious Rare Inherited Blood Disorder

Blood disorder

Caption: Sherryn Lindsay (left), has seen a huge improvement in her quality of life since meeting Dr Frank Firkin.

Sherryn Lindsay has been sick since she was six weeks old. Initially diagnosed with neutropenia, low counts of the white blood cells that kill bacteria, she has struggled with a wide range of other health problems and numerous life-threatening bacterial infections.

Recently, Sherryn learned she has WHIM syndrome, a rare congenital immune deficiency that causes Warts, Hypogammaglobulinemia, Infections and Myelokathexis, caused by the trapping of neutrophils in bone marrow so they cannot flow out into the blood. This has caused her to have warts, hearing loss, permanent lung damage and a chronic cough.

Previously, there was no effective treatment, but Dr Frank Firkin, a Haematologist at St Vincent’s, is leading the charge to cure this extremely rare condition.

Sherryn is now part of a world-first trial carried out in two sites across the world, led in Australia by Dr Firkin, using an anti-AIDS drug.

Dr Firkin became interested in the condition when one of his patients, Leanne, a pharmacist at St Vincent’s, suffered from eight episodes of pneumonia in eight months. A sputum test identified an opportunistic bacterium as the cause.

“Leanne had suffered from numerous serious infections throughout her life”, Dr Firkin says.

He performed a bone marrow test, and it showed typical features of WHIM syndrome.

“It’s like you have a car but can’t drive anywhere because it is stuck in the garage.”

Later a special mutation was found that caused neutrophils to be trapped in bone marrow. Leanne was the first in Australia to have the genetic test to confirm WHIM syndrome, which was conducted at St Vincent’s.

“There are around 150 cases of WHIM syndrome worldwide, and there is a 50 per cent chance WHIM patients will pass the disorder onto their children, so it is critical we find a cure,” Dr Firkin says.

When he heard about Mavorixafor, a drug used in the treatment of AIDS that could work in this rare condition, Dr Firkin was keen to bring the trial to St Vincent’s for his patients.

“This treatment was very promising, as it interferes with binding of the AIDS virus to cells,  but also interferes with the sustained binding that causes neutrophils to stick in the bone marrow in WHIM patients,” he explains.

The new treatment involves a daily dose of oral medication that releases white blood cells into the blood to fight infection.” Now, after two years, they have had more than a 75 per cent reduction in infections, and none have been severe as in the past. There has also been a reduction in the number of warts in patients taking this drug.”

“The patients are so grateful; it has absolutely changed their lives,” Dr Firkin says.

The results of the trial have just been published in the medical journal, Blood.

Dr Firkin says now that the drug has been deemed medically safe, it is hoped the FDA in USA will grant approval for sale.