Virucidal effect of povidone iodine on COVID-19 in the nasopharynx: A structured summary of a study protocol for an open-label randomized clinical trial

Trials. 2021 Jan 4;22(1):2. doi: 10.1186/s13063-020-04963-2.


Objective: General: To assess the virucidal efficacy of povidone iodine (PVP-I) on COVID-19 virus located in the nasopharynx Specific: i. To evaluate the efficacy of povidone iodine (PVP-I) to removeCOVID-19 virus located in the nasopharynx ii. To assess the adverse events of PVP-I TRIAL DESIGN: This is a single-center, open-label randomized clinical trial with a 7-arm parallel-group design.

Participants: The study will be conducted at Dhaka Medical College Hospital, Dhaka, Bangladesh.

Inclusion criteria: All RT-PCR-confirmed COVID-19 cases aged between 15-90 years with symptoms for the past 4 days will be screened. Those who give informed consent, are willing to participate, and accept being randomized to any assigned group will also be considered for final inclusion.

Exclusion criteria: Patients with known sensitivity to PVP-I aqueous antiseptic solution or any of its listed excipients or previously diagnosed thyroid disease or who had a history of chronic renal failure: stage ≥3 by estimated glomerular filtration rate (eGFR) Modification of Diet in Renal Disease (MDRD) or had acute renal failure (KDIGO ≥stage 2: creatinine ≥2 times from the baseline) or patients who required invasive or noninvasive ventilation or planned within the next 6 hours were considered for exclusion. Moreover, lactating or pregnant women will also be restricted to include here.

Intervention and comparator: This RCT consist of seven arms: Arm-1 (intervention group): will receive povidone iodine (PVP-I) nasal irrigation (NI) at a concentration of 0.4% Arm-2 (intervention group): will receive PVP-I nasal irrigation at a concentration of 0.5% Arm-3 (intervention group): will receive PVP-I nasal irrigation at a concentration of 0.6%. Arm-4 (intervention group): will receive PVP-I nasal spray (NS) at a concentration of 0.5%. Arm-5 (intervention group): will receive PVP-I nasal spray at a concentration of 0.6%. Arm-6 (placebo comparator group): will receive distilled water through NI Arm-7 (Placebo comparator group): will receive distilled water through NS The intervention arms will be compared to the placebo comparator arms. Other supportive and routine care will be the same in both groups.

Main outcomes: The primary outcome is the proportion of cases that remain COVID-19 positive following the intervention. It will be assessed from 1 minutes to 15 minutes after the intervention. Any occurrence of adverse effects following the intervention will be documented as a secondary outcome.

Randomization: The assignment to the study (intervention) or control (comparator) group will be allocated in equal numbers through randomization using random number generation in Microsoft Excel by a statistician who is not involved in the trial. The allocation scheme will be made by an independent statistician using a sealed envelope. The participants will be allocated immediately after the eligibility assessment and consenting procedures.

Blinding (masking): This is an open-label clinical trial, and no blinding or masking will be performed.

Numbers to be randomized (sample size): A total of 189 confirmed cases of COVID-19 will be randomized into seven groups. In each arm, a total of 27 participants will be recruited.

Trial status: The current trial protocol is Version 1.5 from September 10, 2020. Recruitment began September 30, 2020 and is anticipated to be completed, including data analysis by February 28, 2021.

Trial registration: The trial protocol has been registered in the on September 16, 2020. NCT Identifier number: NCT04549376 .

Full protocol: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting the dissemination of this material, the familiar formatting has been eliminated; this letter serves as a summary of the key elements of the full protocol.

Keywords: COVID-19; DMC; Nasal Irrigation; Nasal spray; Povidone Iodine; Protocol; Randomized clinical trial.

Publication types

  • Clinical Trial Protocol
  • Letter

MeSH terms

  • Administration, Intranasal
  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Infective Agents, Local / administration & dosage*
  • Bangladesh
  • COVID-19 / diagnosis
  • COVID-19 / drug therapy*
  • COVID-19 / virology
  • Clinical Trials, Phase II as Topic
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nasal Lavage
  • Nasal Sprays
  • Nasopharynx / drug effects
  • Nasopharynx / virology*
  • Placebos / administration & dosage
  • Placebos / adverse effects
  • Povidone-Iodine / administration & dosage*
  • Povidone-Iodine / adverse effects
  • Randomized Controlled Trials as Topic
  • SARS-CoV-2 / drug effects*
  • SARS-CoV-2 / isolation & purification
  • Treatment Outcome
  • Young Adult


  • Anti-Infective Agents, Local
  • Nasal Sprays
  • Placebos
  • Povidone-Iodine

Supplementary concepts

  • COVID-19 drug treatment

Associated data