This study evaluates the effect of intramuscular injected methylprednisolone treating birch pollen induced rhinitis compared to placebo.

The study was an interventional single center double-blinded human randomized trial with two groups treated parallel.The first group received an intramuscular injection of Methylprednisolone 40 mg/ml 2ml x 1 as a single dose. The second group received an intramuscular injection of NaCl 0,9 mg/ml 2ml x 1 as a single dose. Symptom score and the use of medication was registered daily during the pollen peak of the season, using an electronic diary. The study was conducted during the spring of 2019.

Inclusion Criteria:

• Severe birch pollen induced allergic rhinitis.
• Signed informed consent according to International Council of Harmonisation/Good Clinical Practice, and national/local regulations.
• Women of considered childbearing potential (WOCBP) will only be included after a negative highly sensitive pregnancy test according to CTFG recommendations.

Exclusion Criteria:

• Pregnancy or nursing.
• Autoimmune or collagen disease.
• Cardiovascular disease.
• Hepatic disease.
• Renal disease.
• Cancer.
• Upper airway disease (non-allergic sinusitis, nasal polyposis, chronic obstructive- and restrictive lung disease).
• Medication with a possible side-effect of interfering with the immune response.
• Previous immuno- or chemotherapy.
• Chronic disease.
• Major metabolic disease.
• Alcohol or drug abuse.
• Mental incapability of coping with the study.
• Known or suspected allergy to the study product.
• Suspicion of or confirmed bacterial infection.
• Known allergy to the study drugs, "rescue medication".

IPD of symptoms and use of medication during the trial will be part of the publication

Publication planed during 2021.

The data was published in Scientific reports (found in supplements) 2023