issue with the adaptor/ noticed that there is a great flake almost like a slightly, like a broke out whole piece of plastic from the vial top or cortex just slightly; This is a spontaneous report received from a contactable reporter(s) (Pharmacist) from product quality group.  A patient (no qualifiers provided) received rsv vaccine prot.subunit pref 2v (ABRYSVO), as dose number unknown, single (Lot number: HF7708, Expiration Date: Feb2025) for immunisation; for immunisation. The patient's relevant medical history and concomitant medications were not reported. The following information was reported: DEVICE BREAKAGE (non-serious), outcome "unknown", described as "issue with the adaptor/ noticed that there is a great flake almost like a slightly, like a broke out whole piece of plastic from the vial top or cortex just slightly".  The reporter considered "issue with the adaptor/ noticed that there is a great flake almost like a slightly, like a broke out whole piece of plastic from the vial top or cortex just slightly" not related to rsv vaccine prot.subunit pref 2v. Causality for "issue with the adaptor/ noticed that there is a great flake almost like a slightly, like a broke out whole piece of plastic from the vial top or cortex just slightly" was determined associated to device constituent of rsv vaccine prot.subunit pref 2v (malfunction).  Additional information: ABRYSVO NDC number: 0069034401, UPC number: 300690344010. He was about to administer the RSV ABRYSVO vaccine and he is having an issue with the adaptor. So, he was trying to when he got it ready to put it in, there was an issue. He was inquiring, trying to see if he could use a 5-micron filter to go ahead and administer, thinks there was an issue or defect with the adapter while administering it. When probed if there was an issue with the ABRYSVO vaccine, he was administering the ABRYSVO vaccine and he has quite an issue with the adaptor, and he is trying to see if he is able to use a 5-micron filter, if that is correct to use. He needs the advice on the issue that he was having with the adapter there, that little grey on the adapter, little syringe cap - that may be where he was having issues with the vial adaptor. Thinks may be the syringe cap on he was having issues and he just wants to make sure that the 5 microns filter is correct to use. They put the diluent in, put the bio adapter on top and punctured it. Meant, put the liquid in and then when they were checking it, noticed that there is a great flake almost like a slightly, like a broke out whole piece of plastic from the vial top or cortex just slightly. When clarified if the vaccine was administered to any patient, no, it wasn't; just watched at the vial if there was still a patch with diluent still attached, did not pulled back or anything, just paused and said, "oh, it is not good." Would like to administer this vaccine because did not want to lose the cost of the vaccine but at the same time, wanted to make sure correctly as in terms of running out of little piece of vial from coming out of the pen. Still, was looking at possibly using a 5 micron, but does not know if the RSV molecule itself would be stopped by the filter and would not be able to pass through.  The information on the batch/lot number for rsv vaccine prot.subunit pref 2v  has been requested and will be submitted if and when received.