Canine Lymphoma Treatment with Asparaginase (Elspar)

Asparaginase is a protein that is sometimes used to treat canine lymphoma, or cancers that affect a dog's white blood cells and immune system. Marketed under the brand name anti-cancer drug Elspar, asparaginase is also known as the enzyme L-asparaginase.

Dogs diagnosed with lymphoma may be prescribed chemotherapy treatments of asparaginase to help destroy the cancerous lymphocytes, or white blood cells, that are responsible for the disease. Although caring for a pet with canine lymphoma can be difficult and distressing, learning about treatment options such as Elspar may assist you with important decisions on how to manage your dog's disease. Here is a summary of how asparaginase works, including guidelines for its use and its potential side effects.

How Does Asparaginase Treatment Work?

Asparaginase is a protein that occurs naturally in some plants, like asparagus, as well as certain bacteria and animals. It plays an important role in the break down of the amino acid asparagine into aspartic acid, which helps support the healthy function of the central nervous system. Without asparagine, cells will die. Healthy cells are able to generate their own asparagine, while those affected by lymphoma and other cancers cannot produce their own supply. By introducing asparaginase into the system through chemotherapy, the already dwindling amount of asparagine contained in the cancer cells breaks down even further. Since the cancer cells are unable to replenish their supply of asparagine, they eventually die.

Possible Side Effects of Asparaginase

Although chemotherapy may produce several unwanted effects in people, some animal medical specialist believe that dogs, by comparison, have less risk for adverse responses. Despite this, some dogs may experience side effects while receiving asparaginase treatments, including:

  • Vomiting
  • Loss of appetite
  • Exhaustion
  • Diarrhea
  • Increased blood sugar levels
  • Mild anemia
  • Allergic or anaphylactic response—generally rare

Guidelines for Asparaginase Use

Asparaginase used in chemotherapy treatments is often derived from cultures of E. coli bacteria. Although it is not FDA-approved for use in dogs, it is available by prescription from many veterinarians. It may be administered as an injection or, in some cases, intravenously. It is available in the United States under the brand name Elspar (Merck & Co Inc.). Determining specific doses of asparaginase and the duration of treatment may depend on an individual dog's physical condition and medical history. Since long-term use of asparaginase may produce drug resistance, it may be used in combination with other forms of chemotherapy.

Asparaginase may not be suitable for dogs that are pregnant or nursing. Caution should also be used regarding the use of the drug in animals with known allergies or sensitivities to asparaginase. Due to the risk of possible drug interactions, you should advise your veterinarian if your dog is taking any additional medications or remedies. You may also want to avoid asparaginase therapy if your dog has a history of liver, kidney, blood or pancreatic disorders. Animals with certain gastrointestinal or neurological conditions may also be at risk for potential complications while taking asparaginase.

Learning that your dog has lymphoma or a related cancer can be unsettling. Although the situation is challenging, treatments like asparaginase chemotherapy may offer hope for extending the quality of life for your pet. Understanding how this advanced medicine works may help make decisions regarding treatment a little easier.