The HCP stated the patient did no experience any adverse issues or side effects from the administered dose of PROQUAD; A HCP called to inquire about the viability of an expired dose of PROQUAD (X018814 01/07/2025) that was administered to a patient on 01/24/2025.; The HCP was unsure if the PROQUAD had ever undergone a temperature excursion (TE).; This spontaneous report was received from a nurse and refers to a 4-year-old patient of an unknown gender. The patient’s pertinent medical history, concurrent conditions, drug reactions or allergies were not reported. Concomitant medications included sterile diluent (MERCK STERILE DILUENT). On 24-JAN-2025, the patient was vaccinated with an expired and potentially improper storage dose of measles, mumps, rubella and varicella (oka-merck) virus vaccine live ([rHA recombinant human albumin]) (PROQUAD) injection, lot #X018814; which has been verified to be valid for measles, mumps, rubella and varicella (oka-merck) virus vaccine live, expiration date: 07-JAN-2025, administered for prophylaxis (strength, vaccination schedule, exact quantity volume, route and anatomical site of administration were not provided) (Expired product administered; Product storage error). The reporter inquired about the viability of this expired dose. In addition, she stated she was not sure if it had ever undergone a temperature excursion (TE) and could not provide more information related to it. The patient did not experience any adverse issues or side effects (no adverse event).