Using the following text, list the top 4 drugs by revenue for Pfizer in 2022?
Pfizer Inc. (/ˈfaɪzər/ FY-zər) is an American multinational pharmaceutical and biotechnology corporation headquartered on 42nd Street in Manhattan, New York City. The company was established in 1849 in New York by two German entrepreneurs, Charles Pfizer (1824–1906) and his cousin Charles F. Erhart (1821–1891).

Pfizer develops and produces medicines and vaccines for immunology, oncology, cardiology, endocrinology, and neurology. The company's largest products by sales are the Pfizer–BioNTech COVID-19 vaccine ($37 billion in 2022 revenues), Nirmatrelvir/ritonavir ($18 billion in 2022 revenues), Apixaban ($6 billion in 2022 revenues), a pneumococcal conjugate vaccine ($6 billion in 2022 revenues), and Palbociclib ($5 billion in 2022 revenues). In 2022, 42% of the company's revenues came from the United States, 8% came from Japan, and 50% came from other countries.

Pfizer was a component of the Dow Jones Industrial Average stock market index from 2004 to August 2020. The company ranks 43rd on the Fortune 500 and 43rd on the Forbes Global 2000.
1. Pfizer–BioNTech COVID-19 vaccine
2. Nirmatrelvir/ritonavir 
3. Apixaban 
4. Palbociclib
You are an expert Q&A system that is trusted around the world. You always answer the user's query in a helpful and friendly way.
Some rules you always follow:
1. If context is provided, you never directly reference the given context in your answer.
2. If context is provided, use the context information and not prior knowledge to answer.
3. Avoid statements like 'Based on the context, ...' or 'The context information ...' or 'The answer to the user's query...' or anything along those lines.
4. If no context is provided use your internal knowledge to answer.
system
(Optional) Context information is below.
----------------
Pfizer Inc. (/ˈfaɪzər/ FY-zər) is an American multinational pharmaceutical and biotechnology corporation headquartered on 42nd Street in Manhattan, New York City. The company was established in 1849 in New York by two German entrepreneurs, Charles Pfizer (1824–1906) and his cousin Charles F. Erhart (1821–1891).

Pfizer develops and produces medicines and vaccines for immunology, oncology, cardiology, endocrinology, and neurology. The company's largest products by sales are the Pfizer–BioNTech COVID-19 vaccine ($37 billion in 2022 revenues), Nirmatrelvir/ritonavir ($18 billion in 2022 revenues), Apixaban ($6 billion in 2022 revenues), a pneumococcal conjugate vaccine ($6 billion in 2022 revenues), and Palbociclib ($5 billion in 2022 revenues). In 2022, 42% of the company's revenues came from the United States, 8% came from Japan, and 50% came from other countries.

Pfizer was a component of the Dow Jones Industrial Average stock market index from 2004 to August 2020. The company ranks 43rd on the Fortune 500 and 43rd on the Forbes Global 2000.
----------------
Answer the following query.
Using the following text, list the top 4 drugs by revenue for Pfizer in 2022?

user
1. Pfizer–BioNTech COVID-19 vaccine
2. Nirmatrelvir/ritonavir 
3. Apixaban 
4. Palbociclib
assistant