The study will investigate the efficacy and safety of subcutaneous interferon alpha -2a to eradicate rhinovirus in patients with primary hypogammaglobulinemia. Patients with hypogammaglobulinemia have persistent rhinovirus infections. Rhinovirus may worsen pulmonary complications. Pegylated interferon alpha with ribavirin appear to effectively clear persistent rhinovirus infections in hypogammaglobulinemia patients.

Patients with primary hypogammaglobulinemia and confirmed respiratory rhinovirus infection will be randomly assigned in a double-blind fashion to receive either

• Group 1: subcutaneous pIFNα2a
• Group 2: subcutaneous placebo Subjects will have scheduled study visits at 1-week and at 2-month after entry to study. In addition, possible bacterial infections will be treated with antibiotics. Each patient will be followed with weekly nasal surveillance samples for 2 months and a symptom diary. Blood draws take place at study entry, 1-week and 2-month time-points.

Inclusion Criteria:

• Adult patients (>18 years),
• primary hypogammaglobulinemia with regular immunoglobulin replacement therapy,
• rhinovirus positive from nasal swab,
• thrombocytes over 90 x109/L,
• Neutrophiles > 1,5 x109/L
• written informed consent.

Exclusion Criteria:

• Participation to another study,
• need for intensive care unit treatment,
• difficulties to understand national language, pregnancy and breastfeeding,
• any somatic, psychiatric or social disease or issue which in the opinion of the investigator makes participation in the trial not being in the best interest of the subject.