Paroxysmal nocturnal haemoglobinuria (PNH) remains a complication seen in up to a half of patients with aplastic anaemia, especially after treatment with immuno-suppressive therapy. This results from complement (an arm of the immune system) mediated destruction of the red blood cells.


A PNH clone is not unusual in patients with aplastic anaemia who have been treated with IST and explains the escape phenomenon of the PNH stem cell in the bone marrow. A study originating from the International PNH registry has shown that Eculizumab – a monoclonal antibody in use for PNH, retains efficacy when combined with IST treatment, irrespective of the sequence of use of these therapies, and their effectiveness is retained even when used concomitantly.