[Press Release Feb. 23, 2021 / Unofficial Translation]



1. Current Marketing Authorization Review Status

□ On February 22, the Ministry of Food and Drug Safety (MFDS, Minister Kim Ganglip) held the meeting of COVID-19 Vaccine Safety and Clinical Efficacy Advisory Committee (hereinafter Advisory Committee) regarding clinical trial results of COMIRNATY Inj., Pfizer Korea’s COVID-19 vaccine.
○ The Advisory Committee meeting is a mandatory procedure of the MFDS to seek advice on clinical, nonclinical, and quality data from various experts prior to consulting the Central Pharmaceutical Advisory Committee.
- Seven expert advisory panel members composed of specialists in infectious diseases, vaccine and clinical statistics participated the Advisory Committee meeting.

2. Clinical Trial Results
< Overview >
□ There have been submission of data from clinical studies conducted in Germany (phase I·II) and from a multi-national clinical studies carried out in six countries* (phase I·I·III) including the U.S. The Advisory Committee evaluated and analyzed the safety and effectiveness data from the latter.
* The U.S., Argentina, Brazil, Germany, South Africa and Turkey
** Immunogenicity Evaluation was carried out in the phase I and II clinical trial conducted in Germany and the U.S.
○ In the multi-national clinical trial, 43,448 participants on average 50 years of age received at least 1 dose of vaccine or placebo. Among the participants, 49.1% (21,324) were women, 20.7% (8,978) had underlying disease such as diabetes or respiratory disease, 34.7% (15,063) were obese and 41.1% (17,846) were aged 55 and older.

< Efficacy >
□ (Preventive Effect) The effectiveness in prevention was evaluated on the 36,523 participants (18,198 vaccine, 18,325 placebo) who were not tested positive of COVID-19 within 7 days after receiving 2 doses of the vaccine or placebo*.
*Placebo: 0.9% saline solution
** 21.9% (8,018) of the participants were aged 65 or older.
○ Preventive effect was evaluated based on comparison and analysis of COVID-19 cases in each group from 7 days after the second dose of the vaccine or placebo. Participants who have more than one clinical symptoms and tested positive for COVID-19 virus were defined as infected.
○ As a result of the evaluation, the vaccine showed 95% of effectiveness in prevention as there were 8 COVID-19 cases in the vaccinated group and 162 cases in the placebo group. Moreover, regardless of age1) and underlying disease2), the vaccine was more than 94% effective.
1) ages 18 to 64: 95.1%; ages 65 and older: 94.7%.
2) with underlying disease: 95.3%; without underlying disease: 94.7%.
○ One vaccine recipient and three placebo recipients had severe COVID-19 disease with symptoms such as decreased oxygen saturation. The case split does suggest protection from severe COVID-19 disease but as the total number of severe cases is small, there are limits to drawing statistical conclusions.
*Severe COVID-19 occurance after receiving at least one dose: the vaccinated group (1), the placebo group (3)
○ (Immunogenicity Evaluation) As an indirect indicator to measure effectiveness, the committee evaluated immunogenicity by examining the number and amount of antigens formed.
○ Binding antibody titer increased more than four fold in all participants after administration of the vaccine reaching 100% of seroconversion rate.
○ Neutralizing antibody titer increased more than four fold after the second dose in all participants reaching 100% of seroconversion rate.

< Safety >
□ Solicited adverse events (local and systemic) were monitored in 8,183 participants (4,093 vaccine, 4,090 placebo) within 7 days following each dose.
○ The most frequently reported local reactions were injection site pain (84.1%), swelling (10.5%) and redness (9.5%). The majority of them were mild to moderate in severity and lasted one or two days since their onset.
○ The most frequently reported systemic adverse reactions were fatigue (62.9%), headache (55.1%). muscle pain (38.3%), chills (31.9%), joint pain (23.6%) and fever (14.2%). The majority of them were mild to moderate in severity, starting within 2 to 3 days after administration and lasted one day.
○ Systemic adverse events tended to be more frequent and severe in the younger than the older age group. Within each group, the frequency and severity was higher after the second dose than the first dose.
*the younger age group (16 to 55 years of age): 82.8%; the older age group (56 years of age and older): 70.6%.
□ A total of 37,586 (18,801 vaccine, 18,785 placebo) participants were subject to evaluation of unsolicited adverse events (a 4 weeks follow-up monitoring). Unsolicited adverse events were reported in 20.8% (3,915/18,801 participants) of the vaccine recipients and the major symptoms included injection site pain (11.2%), fever (6%), fatigue (5.3%), chills (5.3%), headache (4.8%) and muscle pain (4.7%).
○ There was one reporting of drug-related hypersensitivity (urticaria) in vaccine recipients and no vaccine-related anaphylaxis reported during the clinical trial.
○ Among a total of 43,448 participants enrolled in the study, serious adverse events has been reported in 0.6% (126) of vaccine recipients and in 0.5% (111) of placebo recipients. Among them, four serious adverse events, including shoulder injury, were considered as related to vaccine administration.

<< Efficacy and Safety in Individuals Aged 16 to 17>>
□ Regarding individuals aged 16 and 17, evaluation on effectiveness (on 107 subjects) and safety (on 283 subjects) were conducted. The result showed that there was no COVID-19 case in both vaccinated and placebo group.
○ There were adverse events similar to those reported among other age groups (18 to 55 years of age, 55 years of age and older): fever (7.2%), injection site pain (5.8%), chills (2.8%), headache (2.9%) and others. There was no serious adverse drug reaction.

3. Outcome of the Advisory Committee Meeting
<< Administration to Individuals Aged 16 and 17>>
○ The Advisory Committee recommended approval of the vaccine for administration to individuals aged 16 and 17 considering the following:
▲ The vaccine has been proven to be safe and effective in individuals 16 years of age and older in the clinical trials designed to evaluate its safety and efficacy in the age group.
▲ Immune response in adolescents aged 16 and 17 is deemed to be similar to that of adults.
▲ Results from the clinical trials in adults can be used as reference.
▲ In multiple countries including the U.S., E.U. countries, the U.K and Japan, the vaccine has been approved for use in individuals aged 16 and older.

<< Advice on Safety>>
○ The Advisory Committee viewed that the safety profile of the vaccine demonstrated in the clinical trial result is in an acceptable range. Meanwhile, the committee recommended more meticulous monitoring after administration in individuals with medical history of anaphylaxis.

<< Advice on Efficacy>>
○ The panels of the Advisory Committee viewed that the vaccine is effective in preventing COVID-19 as the data in submissions shows effectiveness and maintenance of participants’ immune response, with a higher level of antibody than in the plasma of individuals completely recovered from COVID-19.
○ The panels also advised that after granting marketing authorization, there should be continued follow up and monitoring of safety based on risk management plan and that adverse events occurred in clinical trials should continuously be collected and analyzed.


4. Weekly Plan on Review and Approval
○ The Ministry of Food and Drug Safety is reviewing submissions from Pfizer Korea’s COMIRNATY Inj. including quality control reports and is also taking into consideration of expert advice and recommendation gathered as the outcome of the Advisory Committee meeting.
- On February 25, based on the comprehensive considerations, the MFDS will seek expert advice from the Central Pharmaceutical Advisory Committee on various items including safety, efficacy and matters to be considered when granting marketing authorization. The outcome of the CPAC meeting will be announced on Friday, February 26.