Treatment Name: Avatrombopag (Doptelet®)
How does avatrombopag (Doptelet®) for ITP work?
Immune thrombocytopenic purpura, or ITP, causes decreased plateltet counts through decreased production or increased destruction of platelets.
Avatrombopag (Doptelet®) is designed to increase platelets in your bloodstream by stimulating the cells in your bone marrow that make them. Specifically, avatrombopag binds to cells known as megakaryocytes (mega-care-e-o-sites) causing them to produce more platelets. When first beginning therapy with avatrombopag, it often takes 5 - 8 days to see an initial rises in platelets, with the peak effect (highest platelet count) occuring after taking avatrombopag for 10 - 14 days.
Goals of avatrombopag (Doptelet®) therapy:
Avatrombopag is taken to increase platelets in the blood stream when platelets are low. It is usually taken with the goal of increasing platelets to a safe range to prevent spontaneuos bleeding, such as above 50 k/μL, and is not taken with the goal of "normalizing" the platelet count (normal platelet count = 150 - 400 k/μL (range may vary by lab). Avatrombopag may be used for patients with chronic ITP that have low platelet counts after receiving a previous treatment such as dexamethasone, prednisone, immune globulin, or for patients with low platelets after spleen removal (history of splenectomy).
Note: If a procedure is scheduled to take place, such as surgery, your doctor may advise that the platelet count be increased above 100 k/μL before the procedure takes place.
Avatrombopag (Doptelet®) is only available as a prescription drug and is dispensed through a specialty pharmacy.
- Usual starting dose for ITP: avatrombopag (Doptelet®) 20 mg oral tablet by mouth every day with food
- Note: unlike ELtrombopag (Promacta®), AVAtrombopag is taken WITH food
Avatrombopag is usually taken at home by the patient. Treatment is continued until the drug no longer works or until unacceptable side effects occur.
Important note regarding the dose of avatrombopag (Doptelet®):
- If the platelet count rises too high (above the desired range), your doctor may recommend that you decrease the number of times per week that you take avatrombopag (Doptelet®) per instructions available in the avatrombopag (Doptelet®) package insert, or the dose (in milligrams) of each tablet you take.
- Do not decrease the amount of avatrombopag (Doptelet®) without asking your doctor as your platelet count could potentially drop back to unsafe levels.
Note: Individual doses may vary based upon your Doctor's recommendation, or drug availability.
In clinical studies of patients with ITP, the most commonly reported avatrombopag (Doptelet®) side effects are shown here:
A note about side effect percentages
- Bruising (40%)
- Headache (30%)
- Upper respiratory tract infection (example: sinus infection) (23%)
- Nose bleed (17%)
- Bleeding from gums (17%)
- Small bleeds underneath the skin [petechiae] (15%)
- Fatigue (15%)
- Sore throat (13%)
- Joint pain (11%)
- High blood pressure (11%)
- Vomiting (4%)
Between 2 - 8% (2 to 8 out of 100) of patients discontinue avatrombopag (Doptelet®) due to unacceptable side effects.
Note: Of patients who experienced blood clots after taking avatrombopag, the majority of these patients had multiple risk factors for developing a blood clot.
Importantly, not all people who experience a side effect from avatrombopag (Doptelet®) will experience it in the same way. It may be mild in some or severe in others, depending upon the individual. Everybody is different. Additionally, side effects may vary over time. For some, side effects may be a reason to delay or switch treatment, reduce the dose, or avoid future treatment with a certain medication altogether.
Side effects may be treatable when they occur or preventable by taking certain medications before they happen. When medications are taken to prevent a problem, this is known as prophylaxis, or "prophy" for short.
After starting treatment with avatrombopag (Doptelet®), be sure to come back and watch all of the side effect videos shown below. Each of these videos contain valuable information about side effect management that will hopefully help you to both feel better and stay out of the hospital.
How often is monitoring needed?
Labs (blood tests) may be checked before treatment with avatrombopag (Doptelet®), then weekly until stable, then monthly thereafter or as directed by your doctor. Labs often include: Complete Blood Count (CBC), Comprehensive Metabolic Panel (CMP), plus any others your doctor may order.
How often is imaging needed?
Imaging is not typically needed to monitor response or side effects from avatrombopag (Doptelet®); however, imaging may be used if there are concerns for bleeding. Imaging may include: magnetic resonance imaging (MRI) or computerized tomography (CT) scans.
How might blood test results/imaging affect treatment?
Depending upon the results, your doctor may advise to continue avatrombopag as planned, reduce the dose of future treatments, reduce the number of times per week Avatrombopag (Doptelet®) is taken, delay the next dose until the side effect goes away, or switch to an alternative therapy. Do not alter the dose or frequency of avatrombopag without talking with your doctor first as this could potentialy lead to a drop in platelet count which increases the risk of bleeding.
- Take Avatrombopag (Doptelet®) at the same time each day. If you miss a dose, take it as soon as you remember, unless it is near the time of the next dose. Do not take 2 doses at the same time to make up for a missed dose, unless instructed by your doctor. Keep a journal of missed doses so that your doctor knows how to adjust your dose or frequency of Avatrombopag (Doptelet®)
- Do not stop taking Avatrombopag (Doptelet®) without instruction from your doctor. When discontinuing avatrombopag, the platelet count will need to be monitored for at least 4 weeks after stopping therapy
- Avatrombopag may increase your risk of experiencing blood clots. Contact your doctor if you experience any symptoms of a blood clot such as severe shortness of breath, chest pain, or swelling, redness and pain in your arms or legs
- A pharmacist should ALWAYS review your medication list to ensure that drug interactions are prevented or managed appropriately
- Clinical trials may exist for ITP. Ask your doctor if any studies are currently enrolling in your area. If not, go to clinicaltrials.gov to search for other centers offering study medications
Patient Assistance & Co-payment Coverage
Patients under the age of 65 years, or those with private insurance plans:
If you have insurance and are looking for patient assistance or copay assistance for Avatrombopag (Doptelet®), we have provided links that may help.
Visit our Patient Assistance page and click the links to various patient assistance programs for help paying for Avatrombopag (Doptelet®). Depending upon your income, they may be able to help cover the cost of:
For Branded medications (may be available for generic medications too), check with the manufacturer to determine if a co-pay card is offered and if it could reduce your monthly copay.
- If you are uninsured, check with the manufacturer to determine if you are eligible to receive medication at no cost.
Medicare and Medicaid patients (Patients 65 years or older):
The clinic providing treatment will likely pre-authorize medications and immune therapies such as Avatrombopag (Doptelet®) and are the best source to help you understand drug cost.
- Ask to speak with a patient assistance technician or financial counselor at the clinic or hospital administering this therapy.
What is Emotional Wellness?
Emotional wellness is having a positive outlook balanced with a realistic understanding of current life events. This requires both an awareness and acceptance of your emotions. It is with this knowledge that you can develop a plan to take the necessary actions to positively impact your life.
Emotional wellness uses an ongoing process to continually reflect on the stressors of life in a constructive manner to move forward and create happiness.
Because emotional wellness is deeply connected with physical, social, and spiritual wellness, pursuing it often becomes particularly difficult in times of major illness. Despite this difficulty, working toward emotional wellness has been connected to improved treatment outcomes and a higher likelihood of achieving goals of therapy.
Learn more about pursuing emotional wellness while receiving treatment with Avatrombopag (Doptelet®)
What is Immune Thrombocytopenic Purpura (ITP)?
A disorder where platelets decrease in number due to decreased production in the bone marrow and increased destruction in the blood. This can lead to an increased risk of spontaneous bruising or bleeding (without injury), especially when the platelet count drops below 30,000 cells per microliter of blood.
I = Immune, ITP is caused by a disturbance in the immune system
T = Thrombocytopenic, a medical term meaning low platelet count
P = Purpura, a type of bleeding in the skin
ITP is NOT a cancer, but it is commonly managed by hematologists (blood doctors) who often treat blood cancers as well. ITP is an uncommon condition and may be caused by auto-immune disorders, infections, certain medications, or pregnancy. However, in many cases, a cause cannot be identified which gives rise to its other name-idiopathic (meaning “cause unknown”) thrombocytopenic purpura. Although ITP may spontaneously resolve, for some patients lifelong therapy may be needed.
The effectiveness of medications may depend upon the causes of ITP and the ability to remove these causes, or whether a splenectomy (removal of the spleen) has been performed, or is able to be performed.
Deciding on a treatment for ITP is in a way like buying, owning, and driving a car. Think about the following similarities to help you understand which treatment is right for you:
BUYING: "0 - 50 time" (0 to 50 k/µL platelets, instead of 0 - 60 m.p.h) is an important performance feature
Once the platelet count exceeds 50 k/µL, bleeding episodes are rare. Therefore, the time it takes to go from very few platelets to a platelet count over 50 k/µL matters. In general, steroids such as prednisone and dexamethasone have the fastest "0 - 50" time.
- Although exceptions, the thrombopoeitin receptor agonists romiplostim and eltrombopag usually have a 0 - 50 k/µL platelet time of 1 - 2 weeks
- Although exceptions, one-half of rituximab recipients have a 0 - 50 k/µL platelet time below 5.5 weeks, and the other half over 5.5 weeks. The response to rituximab is often unpredictable
OWNING: Warranty offered?
A 5-year bumper-to-bumper warranty helps us worry less about something breaking or going wrong with our vehicle after we buy it. Likewise, not all medications used for ITP have a long-lasting effect in keeping the platelet count above 50 k/µL.
- When it works, rituximab can work for 1 - 2 years, but lasting responses beyond two years are rarer. The 5 year rituximab response rate is estimated at 20 - 25%. When the rituximab "warranty" runs out and platelets fall, patients with ITP that had a long lasting response to rituximab may respond to another course of therapy. Certain insurances require the platelet count to be less than 30 k/µL before it will be covered.
- When they work, the thrombopoeitin receptor agonists romiplostim and eltrombopag generally have lasting effect beyond that of rituximab. The "warranty" period where the platelet count remains above 50 k/µL often lasts 2 years or longer
DRIVING: Cruise control optional?
The ability for a treatment to maintain the platelet count within the goal range is similar to setting the cruise control on a car.
- Steroids are given in a pulse (example: dexamethasone daily for 4 consecutive days) or given daily for several weeks (example: prednisone), then decreased over several weeks and eventually discontinued a few months after it is started. As a result, when steroids are no longer taken there is a chance for ITP to relapse
- Because eltrombopag and romiplostim are administered continuously, these medications have the highest likelihood of keeping the platelet count in the goal range for the long haul
- Rituximab is typically given once weekly for 4 doses, and usually takes several weeks to determine if it is working (see above), therefore it is difficult to predict who will have a lasting response to this therapy
NOTE: Treatment Options listed below are not all-inclusive. Other treatments may be available. ChemoExperts provides drug information and does not recommend any one treatment over another. Only your Doctor can choose which therapy is appropriate for you.
1) Jurczak W, Chojnowski K, Mayer J, et al. Phase 3 randomised study of avatrombopag, a novel thrombopoietin receptor agonist for the treatment of chronic immune thrombocytopenia. Br J Haematol. 2018;183:479-490.
What is a CBC?
A Complete Blood Count (CBC) is a frequently ordered blood test that tells clinicians the status of your: 1) White blood cell count, 2) Hemoglobin, and 3) Platelet count at the time the test was taken.
1) White blood cell count (WBC): is used to determine infection risk, or response to chemotherapy. Certain chemotherapy agents may harm our good infection-fighting cells. Sometimes chemotherapy may need to be delayed to allow these cells to recover.
2) Hemoglobin: is used to determine if someone is anemic. Anytime the hemoglobin is below 12 g/dL, the person is said to be anemic. Red blood cell transfusions, and sometimes iron can be given to restore the hemoglobin level, but anemia treatment should always aim at treating the underlying cause or condition.
3) Platelet count: is used to determine if the risk of bleeding is increased or if a platelet transfusion is required to prevent bleeding. Certain medications that increase bleeding risk, such as: aspirin, certain chemotherapy agents, and blood thinners, may need to be stopped temporarily until the platelet count is within a safe range.
What is a CMP?
A Comprehensive Metabolic Panel (CMP) is a frequently ordered blood test that tells clinicians the status of your: 1) Electrolytes & Acid/Base status, 2) Kidney function, 3) Liver function, 4) Blood sugar, and 5) Calcium at the time the test was taken. It is commonly used to monitor liver and kidney function when beginning new medications such as chemotherapy. A total of 14 tests are run simultaneously and are shown below.
Electrolytes & Acid/Base status:
1) Sodium, 2) Potassium, 3) Carbon dioxide, 4) Chloride
5) BUN (blood urea nitrogen), 6) Serum creatinine (Scr)
7) AST, 8) ALT, 9) Total bilirubin, 10) Alk Phos, 11) Albumin, 12) Total protein
13) Serum glucose
14) Serum calcium
What is Specialty Pharmacy?A pharmacy that manages the handling and services for drugs used by patients with rare or chronic diseases. This has expanded in the last several years to include very expensive drugs used to treat cancer, mainly oral cancer medications or injections that can be taken at home.
A note about side effect percentagesThe number you see next to the percent sign (%) means how many people out of 100 are likely to experience this side effect.
For example, if the side effect is reported to occur in 8% of patients, this means that roughly 8 out of 100 people receiving this treatment will experience this side effect.