KEYTRUDA vs PEGASYS

Independent side-by-side comparison.

Rated against independent regulatory sources·Last updated August 21, 2026·How we rate

Possible drug interaction. KEYTRUDA and PEGASYS are different prescription medicines. Combining or switching between them can cause interactions — talk to a pharmacist or prescriber before making changes. This page is not medical advice.

Attribute	KEYTRUDA	PEGASYS
Rating	70/100	New
Pharmacy pays	—	—
Type	RX	RX
Active ingredient	PEMBROLIZUMAB	PEGINTERFERON ALFA-2A
Manufacturer	Merck Sharp Dohme	Pharmaand Gmbh
Dosage forms	Injectable	Injectable
Drug class	Programmed Death Receptor-1 Blocking Antibody	—
Boxed warning	None	Boxed warning
Treats	Malignant Mesothelioma, Biliary Tract Neoplasms, Urinary Bladder Neoplasms	Brain Neoplasms, Renal Cell Carcinoma, Cryoglobulinemia

keytruda pegasys

Rating

70/100

New

Pharmacy pays

—

Type

Active ingredient

PEMBROLIZUMAB

PEGINTERFERON ALFA-2A

Manufacturer

Merck Sharp Dohme

Pharmaand Gmbh

Dosage forms

Injectable

Drug class

Programmed Death Receptor-1 Blocking Antibody

—

Boxed warning

None

Boxed warning

Treats

Malignant Mesothelioma, Biliary Tract Neoplasms, Urinary Bladder Neoplasms

Brain Neoplasms, Renal Cell Carcinoma, Cryoglobulinemia

Frequently asked questions

What is the difference between Keytruda and Pegasys?

Keytruda contains Pembrolizumab, while Pegasys contains Peginterferon Alfa-2a — they have different active ingredients.

Ratings are based on FDA regulatory (recall-safety) data. This comparison is for general reference only — not medical advice. Always consult a licensed professional before choosing or switching a medication.