Background Allergic rhinitis and Asthma are considered as ‘one airway disease’. Theophylline has been used as a bronchodilator in asthma for decades but more recently its anti-inflammatory properties have been identified. We hypothesise that treatment with low dose theophylline in patients with persistent allergic rhinitis is likely to improve the total nasal symptom scores and there by demonstrate a clinically meaningful difference.
Methods This was a single centre double- blind, randomised, placebo-controlled cross-over study of the effects of theophylline (one capsule of Theophylline 200 mgs as Uniphyllin continus twice a day for 4 weeks) in 21 patients with persistent allergic rhinitis in Norwich, U. K. Reference: NCT0113278. Primary outcome was Total Nasal Symptom Score (TNSS) after each intervention period. Secondary endpoint measures were differences in the domiciliary average total nasal symptom score, differences in nasal peak inspiratory flow (PNIF), differences in domiciliary nasal peak inspiratory flow and difference in Sino-Nasal Outcome Test (SNOT)-22.
Results Primary Endpoint
There was no significant (p = 0.276) difference in Total Nasal Symptoms scores during Theophylline treatment period and placebo period, mean (SD) (Table). The intention-to-treat analysis results were in keeping with the per protocol analysis.
Secondary End points
PNIF in the Theophylline period was 112.38(±43.49) compared to the placebo period 122.86(±53.77), p = 0.171 (Table). There was no change in SNOT-22 (p = 0.867) between treatment periods but there was a non-significant improvement with Theophylline (39.00 ± 19.78) compared to placebo (38.00 ± 19.63) treatment period. There was a non-significant improvement in the domiciliary total nasal symptom scores (TNSS) between Theophylline (3.53 ± 2.35) and placebo (2.81 ± 2.46). Nasal scrape samples were stained with HDAC2 antibodies and the signals were very week.
Conclusion This is the first study evaluating Theophylline in persistent rhinitis. Low-dose Theophylline had no significant effects on Total nasal Symptom scores; Rhinosinusitis symptoms and nasal patency assessed using peak nasal inspiratory flow. There was a non-significant improvement in the total nasal symptom scores and sino-nasal outcome test and domiciliary nasal scores.