Modified Ketogenic Diet in Patients With McArdle Disease Part B

  • days left to enroll
  • participants needed
  • sponsor
    Rigshospitalet, Denmark
Updated on 23 January 2021


McArdle disease, glycogen storage disease type V, is a rare metabolic disease. Affected individuals are unable to utilize sugar stored as glycogen in muscle. Investigators hypothesize that a modified ketogenic diet could be a potential treatment option, by providing ketones as alternative fuel substrates for working muscle.

This blinded, placebo-controlled, cross-over study will investigate the potential effects of an optimal modified ketogenic diet found in part A (75% fat, 15%protein, 10%carbohydrates) in patients with McArdle disease compared with a healthy balanced placebo diet (>100grams of carbohydrates per day).


A blinded randomized, placebo-controlled, cross-over study to investigate the effects of a modified ketogenic diet in patients with McArdle disease.

McArdle disease, glycogen storage disease type V, is a rare metabolic disease caused by mutations in the PYGM gene resulting in absence of the enzyme muscle phosphorylase. Affected individuals are unable to utilize sugar stored as glycogen in muscle, leading to exercise intolerance, exercise-induced muscle pain, contractures and rhabdomyolysis. Currently, there are no satisfactory treatment options for McArdle disease. Ketones are feasible fuel alternatives to muscle glycogen when muscle glycogenolysis is blocked as in McArdle disease. A key element of alleviating symptoms in McArdle disease is to provide alternative fuels for energy metabolism. Ketosis can potentially provide alternative fuel substrates by provision of endogenous ketone bodies (KBs) which are desirable fuels for skeletal muscle and brain. Ketosis can be reached by fasting and can be induced by adhering to a modified ketogenic diet, which entails a high-fat, low-carbohydrate diet, which simulates the metabolic effects of fasting.

The study design is a placebo-controlled, blind, cross over design. The study will be carried out at two sites: CNMC (Copenhagen), NHNN (London). Subjects will be randomized 1:1 to receive either a modified ketogenic diet (75% fat, 15%protein, 10% carbohydrates) or a placebo diet (>100grams of carbohydrates per day) first. Subjects will follow the diet for 4 weeks, followed by 2-4 weeks wash-out, followed by 4 weeks on the opposite diet. During the 10-12 weeks trial period, subjects will visit the trial site in London on five occasions. Effects of the diet will be evaluated by improvement in exercise capacity during submaximal exercise test on a cycle ergometer. Subjective improvements will be evaluated by questionnaires and a dietary diary.

If the diet improves exercise capacity, it will provide a safe and cheap treatment option that may lead to reduced risk of muscle injury and enhance quality of life in patients with McArdle disease.

Condition Glycogen Storage Disease Type V
Treatment Ketocal 4:1 liquid Nutricia (intervention), Fortini multifibre Nutrica (placebo)
Clinical Study IdentifierNCT04044508
SponsorRigshospitalet, Denmark
Last Modified on23 January 2021


Yes No Not Sure

Inclusion Criteria

Genetically confirmed GSDV
Patient is willing and able to provide written informed consent prior to participation
Patient is ambulatory
Women in fertile age must be willing to practice the following medically acceptable methods of birth control

Exclusion Criteria

Patient has any prior or current medical conditions that, in the judgment of the Investigator, would prevent the patient from safely participating in and/or completing all study requirements
Pregnancy or breastfeeding
Patient does not have the cognitive capacity to understand/comprehend and complete all study assessments
Patients with porphyria or disorders of fat metabolism (primary carnitine deficiency, carnitine palmitoyltransferase I or II, -oxidation defects etc.)
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact



Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note