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Evaluating the Effects of an Ophthalmic Solution of Coenzyme Q10 and Vitamin E in Open-Angle Glaucoma Patients: A Study Protocol



The CoQun® study is a multicenter, controlled trial aimed to evaluate the neuroprotective effects of Coqun®, an ophthalmic solution of Coenzyme q10 (CoQ10) and Vitamin E (VitE), in patients affected by primary open-angle glaucoma (POAG). Pre-clinical studies and small non-controlled clinical trials have previously shown a potential role of CoQ10 and VitE in glaucoma neuroprotection, both in vitro and in vivo.


Randomized, parallel arm, multicenter, double-blind study. POAG patients with an IOP ranging from 17 to 21 mm Hg on monotherapy with a prostaglandin analogue (PGA) will be considered for study enrollment. Inclusion criteria will be visual field (VF) mean deviation between − 4 and − 10 dB and VF Pattern Standard Deviation between 4 and 10 dB. Eligible patients will be randomized to receive CoQun® (Arm A) or placebo (Arm B), in addition to PGA monotherapy.

Planned Outcomes

Primary outcome will be time to progression, defined as the time between the baseline visit and the visit with confirmed VF progression. A total of 612 patients are planned to be enrolled, to detect a hazard ratio of 0.65, with a power of 80% and an alpha error of 0.05 (two-sided). For study power calculation, 10% non-evaluable patients are assumed. This is the first study investigating, in a randomized, double-blind and controlled fashion, the neuroprotective effects of CoQ10 and VitE in POAG patients.

Trial Registration identifier, NCT03611530.

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The CoQun study is unconditionally supported by Visufarma (Rome, Italy), providing CoQun® to experimental sites and giving economical support for study management. No funding or sponsorship was received for publication of this article.


All named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship for this article, take responsibility for the integrity of the work as a whole, and have given their approval for this version to be published. The contribution of Fondazione Bietti in this study was supported by Fondazione Roma and by the Italian Ministry of Health. The CoQun® Study Group includes the following coauthors: Maurizio Fossarello4; Maurizio Uva5; Luciana Carmassi6; Stefano Gandolfi7; Gemma C Rossi8; Luigi Fontana9; Teresa Rolle10; Daniele Tognetto11; Leonardo Mastropasqua12; Emilio Campos13; Carlo Nucci14; Gianluca Scuderi15; Giorgio Marchini16. 4Ospedale San Giovanni di Dio, Cagliari, Italy. 5Azienda Ospedaliera Universitaria Policlinico Vittorio Emanuele, Catania, Italy. 6Istituto Auxologico Italiano, Milan, Italy. 7Università degli Studi di Parma, Parma, Italy. 8Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. 9Azienda Ospedaliera Arcispedale S. Maria Nuova, Reggio Emilia, Italy. 10Azienda Ospedaliera Universitaria Città della Salute e della Scienza, Torino, Italy. 11Ospedale Maggiore di Trieste, Trieste, Italy. 12Ospedale Clinicizzato SS Annunziata, Chieti, Italy. 13Policlinico Sant’Orsola Malpighi, Bologna, Italy. 14Fondazione Policlinico Tor Vergata, Rome, Italy. 15Ospedale Sant’Andrea, Rome, Italy. 16Azienda Ospedaliera Universitaria Integrata (AOUI), Verona, Italy.


Luciano Quaranta, Ivano Riva, Elena Biagioli, Erica Rulli, Eliana Rulli, Davide Poli and Lorenzo Legramandi have nothing to disclose.

Compliance with Ethics Guidelines

All the procedures performed in studies involving human participants are in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent will be obtained from all individual participants included in the study. The Ethics Committee of the coordinating center (Comitato Etico di Brescia, ASST degli Spedali Civili di Brescia, Italy) and of each involved centers approved the study protocol (see supplementary material). The study has been registered at (NCT03611530).

Data Availability

Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study.

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Correspondence to Luciano Quaranta.

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Quaranta, L., Riva, I., Biagioli, E. et al. Evaluating the Effects of an Ophthalmic Solution of Coenzyme Q10 and Vitamin E in Open-Angle Glaucoma Patients: A Study Protocol. Adv Ther 36, 2506–2514 (2019).

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  • Coenzyme Q10
  • Open-angle glaucoma
  • Ophthalmology
  • Prostaglandin analogue
  • Randomized clinical trial
  • Vitamin E