SCENT2
Trial question
What is the role of theophylline saline nasal irrigation in patients with COVID-19-related olfactory dysfunction?
Study design
Multi-center
Double blinded
RCT
Population
Characteristics of study participants
71.0% female
29.0% male
N = 51
51 patients (36 female, 15 male).
Inclusion criteria: adult patients with chronic olfactory dysfunction following suspected COVID-19 infection.
Key exclusion criteria: history of olfactory dysfunction prior to COVID-19; nasal polyps; prior sinonasal or anterior skull base surgery; neurodegenerative disease; prior seizures or arrhythmia.
Interventions
N=26 theophylline nasal irrigation (400 mg dissolved in 240 mL isotonic nasal saline lavage BID for 6 weeks).
N=25 placebo nasal irrigation (500 mg lactose dissolved in 240 mL isotonic nasal saline lavage daily for 6 weeks).
Primary outcome
Patients who experienced slightly better improvement in clinical global impression-improvement scale
59%
43%
59.0 %
44.3 %
29.5 %
14.8 %
0.0 %
Theophylline nasal
irrigation
Placebo nasal
irrigation
No significant
difference ↔
No significant difference in patients who experienced slightly better improvement in the clinical global impression-improvement scale (59% vs. 43%; AD 15.6%, 95% CI -13.2 to 44.5).
Secondary outcomes
Borderline significantly greater improvement in the University of Pennsylvania Smell Identification Test at 6 weeks (3 vs. 0; AD 3 , 95% CI -0.01 to 6.01).
Borderline significant decrease in QoL-related to smell loss score reduction at week 6 (0.86 points vs. 1.43 points; AD -0.57 points, 95% CI -1.14 to 0).
Borderline significant decrease in parosmia reduction at week 6 (-0.06 vs. 0.06; AD -0.12 , 95% CI -0.24 to 0).
Safety outcomes
No significant difference in adverse events.
Conclusion
In adult patients with chronic olfactory dysfunction following suspected COVID-19 infection, theophylline nasal irrigation was not superior to placebo nasal irrigation with respect to patients who experienced slightly better improvement in the clinical global impression-improvement scale.
Reference
Shruti Gupta, Jake J Lee, Amber Perrin et al. Efficacy and Safety of Saline Nasal Irrigation Plus Theophylline for Treatment of COVID-19-Related Olfactory Dysfunction: The SCENT2 Phase 2 Randomized Clinical Trial. JAMA Otolaryngol Head Neck Surg. 2022 Sep 1;148(9):830-837.
Open reference URL