Promacta (Eltrombopag) - A patient with fluctuating platelets

Promacta (Eltrombopag) increases the platelets count by activating and differentiating the marrow progenitor cells after binding to the thrombopoietin receptors.

It is indicated for the treatment of the following disorders:

  • As first-line therapy in patients with chronic immune / idiopathic thrombocytopenia who have failed first-line therapy with steroids, immunoglobulins and have low platelets following splenectomy.

  • It is also indicated for thrombocytopenia associated with chronic active hepatitis C infections.

  • As a second-line therapy in immune thrombocytopenia in patients who do not respond to steroids prior to splenectomy or in patients with contraindications to surgery.

  • Eltrombopag is FDA approved for the treatment of aplastic anemia in patients who fail to respond to immunosuppression.

  • It has also been recently approved for children one year or older with immune thrombocytopenia wh fail to respond to first-line therapy.


A young male with a variable response to Eltrombopag (Promacta) ...

This is a 22 years of age male patient who presented with epistaxis, gum bleeding, and easy bruisability. The patient was labeled as a case of immune thrombocytopenic purpura. He was advised prednisone 60 mg daily along with calcium supplements and antacids. The patient continued to bleed and his platelet counts remained less than 10000/ul after which he was transfused with platelets on multiple occasions.

The patient was referred to our hospital for further management.

He was continued on prednisone in a dose of 2 mg/kg/day. Although Bone marrow biopsy is not indicated to diagnose immune thrombocytopenia, complicated patients, patients with atypical presentations, those not responding to glucocorticoids, and patients who are scheduled for splenectomy may be advised BMB. So, the patient underwent a bone marrow biopsy which suggested peripheral destruction and hypercellular marrow. He was vaccinated and prepared for splenectomy. Although splenectomy is considered the gold-standard treatment for immune thrombocytopenia, some patients do not respond well. Unfortunately, our patient did not respond to splenectomy. His platelets count remained around 20,000/ul while on prednisone 2 mg/kg/day.


What are the options with us after splenectomy?

Patients with refractory ITP may be advised any of the following medicines depending on the physicians' experience:


Our patient was started on Etromopag (Promacta, Revolade) and the following regimen:


What happened next?

After almost ten days of treatment, the patient's platelets jumped to 12,00,000/ul. Prednisone was reduced to 1 mg/kg, while the other medicines were continued. Platelets of the patient remained around 11,00,000/ul despite reducing the steroids after 3 days. Eltrombopag (Promacta, Revolade) dose was reduced to 25 mg once daily that resulted in a platelet count of around 600,000/ul. After another 10 days, the platelet counts remained elevated and steroids were tapered. The patient was continued on prednisone of 20 mg daily, revolade 25 mg once daily, and azathioprine 50 mg twice daily. His platelet counts remained around 800,000/ul. Eltrombopag was reduced to 25 mg on alternate days.


What happened when eltrombopag was reduced to 25 mg on alternate days?

Reducing the dose of eltrombopag to 25 mg on alternate days resulted in platelet counts of 45000/ul and after a week to 5000/ul. Since the patient was getting eltrombopag from Baitulmaal and he had little of it left, we planned to increase the dose of prednisone.

Despite increasing prednisone to 1 mg/kg, his platelets remained around 10000/ul.

The patient, by himself, restarted eltrombopag at a dose of 50 mg daily and the same response was seen. His platelets jumped again to 12,00,000/ul.

How to manage this patient?

How to adjust the dose of eltrombopag based on the platelet counts?

 

Comments

Dr Farhan
emedz.net@gmail.com

Thanks, Dr. Musaddiq for reading the article. This was a difficult patient that is why I shared his story here. I have seen patients with platelet counts spiking to greater than 10,00,000 with eltrombopag, but I haven't seen so many fluctuations as was in this case. This drug is used as a temporary measure in our setup as one month of treatment costs about Rs. 75,000. We have to look for studies regarding this issue.


Musaddiq_Islam
Musaddiqislam94@gmail.com

Great. I have read the complete article including the one linked in the bottom of the article with the title "how to adjust the dose of eltrombopag based on the platelet count". The drug is, no doubt, a marvellous achievement in the field. But I have a query here: as the dose of eltrombopag is reduced, the platelet count has also proportionally fallen; is there any way that this drug or any other such thrombopoietic drug(s) which could bost the platelet count and then those may be tapered off to zero dose, maintaining a sufficient platelet count, in order to reduce the burden on the pocket of the patient.