Safety and efficacy of 2% pirenzepine ophthalmic gel in children with myopia: a 1-year, multicenter, double-masked, placebo-controlled parallel study

Arch Ophthalmol. 2004 Nov;122(11):1667-74. doi: 10.1001/archopht.122.11.1667.


Objective: To evaluate the safety and efficacy of the relatively selective M(1) antagonist pirenzepine hydrochloride in slowing the progression of myopia in school-aged children.

Methods: This was a parallel-group, placebo-controlled, double-masked study in healthy children, aged 8 to 12 years, with a spherical equivalent of -0.75 to -4.00 diopters (D) and astigmatism of 1.00 D or less. Patients underwent a baseline complete eye examination and regular examinations during a 1-year period. The setting was 13 US academic clinics and private practices. Patients were randomized in a 2:1 ratio to receive 2% pirenzepine ophthalmic gel or a placebo control twice daily for 1 year.

Results: At study entry, the spherical equivalent was mean +/- SD -2.098 +/- 0.903 D for the pirenzepine group (n = 117) and -1.933 +/- 0.825 D for the placebo group (n = 57, P = .22). At 1 year, there was a mean increase in myopia of 0.26 D in the pirenzepine group vs 0.53 D in the placebo group (P < .001). No patients in the placebo group and 13 (11%) of 117 patients in the pirenzepine group discontinued participation in the study because of adverse effects (5 [4%] of 117 due to excessive antimuscarinic effects).

Conclusions: Pirenzepine is effective and relatively safe in slowing the progression of myopia during a 1-year treatment period.

Publication types

  • Clinical Trial
  • Clinical Trial, Phase II
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child
  • Double-Blind Method
  • Female
  • Gels
  • Humans
  • Male
  • Muscarinic Antagonists / adverse effects
  • Muscarinic Antagonists / therapeutic use*
  • Myopia / drug therapy*
  • Ophthalmic Solutions
  • Pirenzepine / adverse effects
  • Pirenzepine / therapeutic use*
  • Refraction, Ocular / drug effects
  • Safety
  • Treatment Outcome
  • Visual Acuity / drug effects


  • Gels
  • Muscarinic Antagonists
  • Ophthalmic Solutions
  • Pirenzepine