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Compare Vemlidy vs. Pegasys

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Vemlidy (tenofovir alafenamide) and Pegasys (peginterferon alfa-2a) are both used to treat hepatitis B, but they have some key differences. Vemlidy is an oral medication taken once daily, while Pegasys is an injection given once a week. Vemlidy is a nucleoside reverse transcriptase inhibitor (NRTI) that works by blocking the virus from making copies of itself, specifically targeting the liver. Pegasys, on the other hand, is an interferon alpha that boosts your immune system to fight the virus. Vemlidy is also used in combination with other medications to treat HIV. Pegasys is used for both hepatitis B and C, but it is no longer recommended for hepatitis C treatment. Both Vemlidy and Pegasys are only available as brand-name medications. Both have serious side effects, but Pegasys has a broader range of potential severe side effects, including mental health issues and risk of serious infections.

Vemlidy (tenofovir alafenamide)
Pegasys (peginterferon alfa-2a)
Vemlidy (tenofovir alafenamide)
Pegasys (peginterferon alfa-2a)
Summary of Vemlidy vs. Pegasys
Summary for Antiretroviral (ARV)
Prescription only
Vemlidy (tenofovir alafenamide), also known as TAF, is a first-choice medication for treating hepatitis B virus (HBV) for adults and children ages 6 years and older weighing at least 55 lbs. Tenofovir alafenamide is also found in combination with other antiretrovirals in medications such as Biktarvy to treat human immunodeficiency virus (HIV). Vemlidy (tenofovir alafenamide) is taken by mouth, typically once daily. Some of the more common side effects of Vemlidy (tenofovir alafenamide) include headache, stomach pain, and cough.
Summary for Interferon alpha
Prescription only
Pegasys (peginterferon alfa-2a) is an interferon alpha. It's used to treat chronic (long-term) hepatitis B and hepatitis C in children and adults, sometimes in combination with other antivirals. Pegasys (peginterferon alfa-2a) is injected under the skin, typically once per week. The most common side effects of this medication include tiredness, headache, and fever.
Indications of Vemlidy vs. Pegasys
Indications for

•Hepatitis B virus (HBV) in people ages 6 years and older weighing at least 55 lbs

Indications for

•Long-term hepatitis C in people ages 5 years and older (in combination with other medications)

•Long-term hepatitis B in people ages 3 years and older
Pros and Cons of Vemlidy vs. Pegasys
Pros and Const for Antiretroviral (ARV)
Pros

•A first-choice medication to treat hepatitis B

•Only taken once a day

•Not as harmful to your kidneys and bones compared to Viread (tenofovir disoproxil fumarate)

•Can be taken by most people with kidney problems

Cons

•Can't take Vemlidy (tenofovir alafenamide) alone if you're co-infected with both HIV and hepatitis B

•Currently only available as brand-name medication

•Must be taken with food

•Can cause worsening of hepatitis B if stopped all of a sudden

Pros and Const for Interferon alpha
Pros

•Given only once per week

•An option for children as young as 5 years old

•Available as a prefilled syringe for easier use

Cons

•Can cause serious side effects, including mental health conditions and risk of serious infection

•No longer recommended for hepatitis C treatment

•Might be difficult for some people to administer correctly
Common Side Effects of Vemlidy vs. Pegasys
Common Side Effects for

•Headache (12%)

•Stomach pain (9%)

•Cough (8%)

•Back pain (6%)

•Tiredness (6%)

•Nausea (6%)

Common Side Effects for
Adults

•Tiredness/fatigue (56%)

•Headache (54%)

•Muscle pain (37%)

•Fever (37%)

•Chills (35%)

•Joint pain (28%)

•Nausea/vomiting (24%)

•Hair loss (23%)

•Pain, swelling, or redness at injection site (22%)

•Anxious/nervousness (19%)

•Difficulty sleeping (19%)

•Depression (18%)

•Loss of appetite (17%)

•Diarrhea (16%)

•Dizziness (16%)

•Stomach pain (15%)

•Itching (12%)

•Pain (11%)

Children

•Flu-like symptoms (fever, cough, short of breath) (81%)

•Stomach problems (nausea, vomiting, diarrhea, stomach pain) (44%)

•Pain, swelling, or redness at injection site (42%)

•Headache (39%)

•Muscle pain (29%)

•Tiredness/weakness (20%)

•Irritated/angry feeling (14%)

•Itching (12%)

•Difficulty sleeping (12%)

•Rash (10%)
Warnings of Vemlidy vs. Pegasys
Common Side Effects for

•Worsening of hepatitis B

•Hepatitis B and HIV coinfection

•Kidney problems

•Liver problems

Common Side Effects for

•Potential harm or death to your unborn baby

•Mental health problems

•Autoimmune disorders

•Stroke or bleeding in the brain

•Infections

•Numbness or pain in your hands or feet (peripheral neuropathy)

•Worsening liver problems and liver failure

•Heart problems

•Low blood cell counts

•Hormone problems

•Eye and vision problems

•Lung problems

•Intestine and pancreas problems

•Delayed growth in children

•Severe allergic and skin reactions
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Key takeaways

Summary of Vemlidy vs. Pegasys

Indications of Vemlidy vs. Pegasys

Pros and Cons of Vemlidy vs. Pegasys

Common Side Effects of Vemlidy vs. Pegasys

Warnings of Vemlidy vs. Pegasys

Prices with our coupons for Vemlidy vs. Pegasys

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