Gained weight; This is a spontaneous report from a contactable consumer reporting for herself. This report was not related to a study. A female patient of an unspecified age received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE; Solution for injection; Lot Number: EN6201; Expiration date was not reported), via an unspecified route of administration, administered in Arm Left on 15Feb2021 11:00 (at the age of 78-years-old) as DOSE 2, SINGLE for COVID-19 immunisation at  Health Dept., Mass vaccination site. Medical history included emphysema, pernicious anaemia and non-tobacco user. It was reported that she never smoked a day in her life and still got emphysema. The patient previously took first dose BNT162B2 (Lot Number: EL9263) in left arm on 25Jan2021 11:00 (at the age of 78-years-old) for COVID-19 Immunisation. The patient was taking COVID 19 vaccine to prevent COVID 19 virus. NDC or Expiry not known for both the doses. Concomitant medications included vitamin b12 [vitamin b12 nos] (VITAMIN B12 [VITAMIN B12 NOS]) taken for pernicious anaemia; albuterol [salbutamol] (ALBUTEROL [SALBUTAMOL]) taken for emphysema, start and stop date were not reported. Caller reported she takes very little medicine including Vitamin B12 shots once every 4 weeks for pernicious anemia. She had an albuterol inhaler that she uses sometimes because she was having emphysema. At the time she received her COVID 19 vaccines she was not getting her Vitamin B12 shots because she was keeping herself shut in. The patient did not received additional vaccines administered on same date of the Pfizer Suspect and Prior Vaccinations (within 4 weeks). The patient did not had any AE following prior vaccinations. On unspecified date in 2021, the patient gained weight. The patient underwent lab tests and procedures which included sars-cov-2 antibody test: negative on 17Jul2021, sars-cov-2 antibody test: negative on 19Jul2021. Caller was asking how she can participate in a clinical study if possible, for the Pfizer COVID Booster Vaccine. The patient received her first Pfizer COVID 19 Vaccine on 25Jan2021. She received the second Pfizer COVID 19 Vaccine on 15Feb2021 at a mass vaccination site in (withheld) and she had no symptoms with either vaccine and she knew that not everyone would have symptoms, and some will. When probing current weight, she reported she had gained weight. Caller voiced that her son was a Nurse Practitioner, all of his patients who received the vaccine have tested positive on the antibody test. Caller was asked if Pfizer has any information on why she may test negative on the antibody testing after being fully vaccinated. A number of people that she knew including friends and family had a COVID 19 antibody test after getting the COVID 19 vaccine and these friends and family members all have positive COVID 19 antibodies except her. She was concerned that the effectiveness of the vaccine has worn off because she was old and was way to 80 years old. Even though she was 79 years old she was still working and teaches on Zoom. She went on 17Jul2021, last Saturday. After she received the negative results, her son suggested she go to (withheld) for a COVID 19 quantitative test and that was also negative. She went to (withheld) on Monday, 19Jul2021. She told her primary healthcare provider that her COVID 19 antibody test was negative, and her doctor said the test was not testing vaccinated people, it was a test only for people who actually had the COVID 19 virus. It was her son who recommended she get the COVID 19 antibody tests. Her daughter-in-law was concerned because the caller received her vaccine at a mass vaccination site and the vaccine had to be kept cold, but she told her daughter-in-law that she did receive both doses. When probing lot number for the first COVID 19 vaccine the caller reports it could be EL9263 or EC9263. She thinks it was EL9263. When probing lot number for the second COVID 19 vaccine she reported it could be EN6201 or EM6201. She received her second COVID 19 vaccine on 15Feb2021 in the left arm. She stated she does not know why everyone was not getting the COVID 19 vaccine because the COVID 19 virus looks like a horrible death. She was concerned over her negative COVID 19 antibodies and would like information on that. Caller was asking if there was a trial for a booster vaccine and how can she be a candidate. AE did not required a visit to Emergency Room or Physician Office. Clinical outcome of the event was unknown.