Safety of subconjunctival allogeneic platelet-rich plasma on normal canine eyes

To determine the safety and tolerance of an allogeneic, pooled freeze-dried platelet-rich plasma (PRP; VetStem PrecisePRP™ Canine) product administered via subconjunctival injection two weeks apart in clinically normal canine eyes.

Allogeneic PRP was reconstituted with sterile water. With topical anesthesia and gentle manual restraint of each dog, 0.2 mL (500 × 10⁶ platelets/mL) of the reconstituted preparation was injected under the dorsal bulbar conjunctiva of the right eye. The procedure was repeated with 0.2 mL of sterile saline (control) under the dorsal bulbar conjunctiva of the left eye. A complete blood count, chemistry profile, and comprehensive physical and ophthalmic examinations were conducted on all dogs at multiple time points to monitor for potential adverse reactions.

No significant adverse effects associated with physical examination, hematologic or ocular parameters were noted at any time point during the study. All allogeneic PRP treated eyes developed a mild to moderate conjunctival hyperemia and chemosis that self-resolved within 48-72 h. Additionally, one eye developed a mild periocular hyperemia that self-resolved within 72 h. No adverse reaction was noted in any saline treated eye.

Allogeneic PRP administered via subconjunctival injection in normal canine eyes appears to be safe and well-tolerated with only transient conjunctival hyperemia and chemosis noted. This study allows for further investigation into the clinical efficacy of subconjunctival allogeneic PRP for canine ocular surface inflammatory disorders.