HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way; No adverse event; This spontaneous case was reported by a pharmacist and describes the occurrence of SYRINGE ISSUE (HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way) and NO ADVERSE EVENT (No adverse event) in a  patient of an unknown age and gender who received mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (batch no. ASKU) for COVID-19 vaccination.    The suspect product included Pre-filled Syringe injection (batch no. Unknown) for COVID-19 vaccination.    No Medical History information was reported.   On an unknown date, the patient received dose of mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (unknown route) Unknown and Pre-filled Syringe (unknown route) at an unspecified dose. On an unknown date, the patient experienced SYRINGE ISSUE (HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way) and NO ADVERSE EVENT (No adverse event). At the time of the report, SYRINGE ISSUE (HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way) and NO ADVERSE EVENT (No adverse event) outcome was unknown.        The action taken with mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (Unknown) was unknown.   For mRNA-1273.815 (SPIKEVAX 2023-2024 PFS) (Unknown), the reporter considered NO ADVERSE EVENT (No adverse event) to be not related. No further causality assessment was provided for SYRINGE ISSUE (HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way).  For Pre-filled Syringe, the reporter considered NO ADVERSE EVENT (No adverse event) to be not related. No further causality assessment was provided for SYRINGE ISSUE (HCP stated they are about to use Spikevax PFS but when she added a 25 gauge 1 inch syringe to the prefilled injector the plunger stopped half way).    Quality complaint number: QE-030630  No concomitant and treatment medications were reported.  Malfunction type was CIRM.  The Device problem code for Spikevax syringe include FDA code 1670, IMDRF code A23 which include Use of Device Problem.  Evaluation and Investigation codes included FDA code 4114, IMDRF code B17 Method / type Device Not Returned. FDA code 3221, IMDRF code C20, result/ findings No Findings Available.  Rationale for no investigation was reported as no additional information was obtained from the complainant, including the affected lot number, pictures or samples, as the consent for the follow-up process was declined. With no additional information available, it is not possible to confirm nor investigate the reported issue. MI questions about needle selection were managed by Combination Product Team and forwarded to the call center in order to inform them to point to CDC guidance for needle selection. After MI review it was confirmed that the information about the needle selection are already available in the MI FAQs and no updates are required (See Attachment section). Therefore, without additional information or batch number, this complaint record will be closed with no further investigation is recommended at this time.   Most recent FOLLOW-UP information incorporated above includes: On 12-Oct-2023: Live significant follow up received. Reference numbers added. On 03-Nov-2023: Significant Follow-up received. PQC Investigation closed report received.