Pembrolizumab (Keytruda) as supportive treatment for melanoma

In 2019, the Institute for Quality and Efficiency in Health Care (IQWiG, Germany) looked into whether adjuvant (supportive) treatment with pembrolizumab (trade name: Keytruda) has any advantages or disadvantages when compared with watchful waiting for people who have had surgery to remove a melanoma and its lymph node metastases.

The manufacturer provided one relevant study. One group of participants (514 people) received pembrolizumab, while another group (505 people) received a placebo. All participants had regular examinations and were in good general health at the beginning of the study. The following results were found for this group of people:

What are the advantages of pembrolizumab?

Recurrence: Here the study suggests that pembrolizumab has an advantage compared with placebo: Only about 31 out of 100 people who received pembrolizumab had a recurrence, compared to nearly 49 out of 100 people in the standard treatment group.

What are the disadvantages of pembrolizumab?

  • Severe side effects: The study suggests that pembrolizumab has a disadvantage here. About 31 out of 100 people had severe side effects, compared to only 19 out of 100 people who received the placebo. These side effects include gastrointestinal diseases, respiratory diseases and immune-mediated side effects. Side effects that are immune-mediated are caused by the attacking its own body.
  • The study suggests that pembrolizumab also has a disadvantage compared with a placebo concerning the following side effects:
    • Infections and parasitic diseases
    • Skin conditions
    • Dry mouth
    • Upper-abdominal symptoms
    • Loss of appetite
    • Muscle and bone pain
    • Breathing problems
  • Treatment stopped due to side effects: Here too, the study suggests that pembrolizumab has a disadvantage compared with a placebo. About 14 out of 100 people who used pembrolizumab stopped their treatment, compared to only about 4 out of 100 people who received a placebo.

What remains unanswered?

Due to the short observation period, effects on life expectancy can't be assessed. The manufacturer did not provide any suitable data on disease-related symptoms, health-related quality of life and overall health.

Institute for Quality and Efficiency in Health Care (IQWiG, Germany). Pembrolizumab (melanoma) – Benefit assessment according to §35a Social Code Book V. Dossier assessment; Commission A19-29. June 27, 2019. (IQWiG Reports; Volume 785).

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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Created on July 18, 2019
Next planned update: 2022


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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