Pitrakinra is a recombinant protein derived from IL-4 that binds to IL-4R[alpha] and acts as an antagonist of IL-4 and IL-13.
Local administration of pitrakinra to the lung of monkeys inhibited allergen-induced airway hyperresponsiveness (AHR), one of the cardinal features of asthma, indicating the therapeutic potential of inhaled pitrakinra in the treatment of atopic asthma.
Inhaled vs subcutaneous effects of a dual IL-4/IL-13 antagonist in a monkey model of asthma. A. Tomkinson, J. Tepper, M. Morton, A. Bowden, L. Stevens, P. Harris, D. Lindell, N. Fitch, R. Gundel, E. B. Getz. Allergy, 2009.
Image source: Crystal structure of human IL-4. Wikipedia, public domain.