The Pharmaceutical Journal
Vol 279 No 7478 p556
17 November 2007

This article
Reprint   Photocopy

  Acrobat Reader

News summary

Pitrakinra study indicates potential of targeted therapy for asthma

Pitrakinra, a recombinant human interleukin-4 variant, may be effective in reducing the symptoms of asthma, two phase IIa trials suggest (Lancet 2007;370:1422).

Interleukin 4 and interleukin 13 are thought to have a critical role in the onset and development of asthma but until now evidence for this has been lacking. Pitrakinra targets these interleukins by competitively inhibiting the interleukin-4R receptor complex.

Researchers conducted two randomised controlled trials using different routes of administration. In the first trial, 24 patients with atopic asthma received pitrakinra 25mg or placebo once daily by subcutaneous injection. In the second, 32 patients with atopic asthma received pitrakinra 60mg or placebo twice daily by nebulisation. Inhaled allergen challenge was carried out at baseline and after four weeks of treatment.

The decrease in forced expiratory volume in one second (FEV₁) during the late phase response to allergen challenge was attenuated after four weeks of treatment with inhaled pitrakinra compared with placebo, say the researchers.

In the subcutaneous pitrakinra group there was a non-significant decrease in FEV₁. However, administration by inhalation conferred a 3.7 times reduction (95 per cent confidence interval 2.08–6.25; P=0.0001).

There were also fewer asthma attacks requiring beta agonist rescue in the subcutaneous pitrakinra group (3 versus 11; P=0.031). Pitrakinra had no effect on the early response to allergen challenge, say the researchers.

“The effects of pitrakinra on late phase asthmatic response are promising when compared with similar studies with other successful anti-inflammatory asthma therapies, including anti-IgE, leukotriene antagonists and inhaled corticosteroids,” the researchers say.

They suggest that future studies of this drug, as well as molecules that specifically inhibit interleukin 13, are warranted in asthma patients of all severities over longer periods.