DOACS

Question 1

Name 4 Direct-acting oral anticoagulants (DOACs)

Answer 1

Apixaban (ELIQUIS)

Dabigatran etexilate (PRADAXA)

Edoxaban (LIXIANNA)

Rivaroxaban (XARELTO)

Question 2

Dabigatran etexilate

Answer 2

Reversible inhibitor of free thrombin, fibrin-bound thrombin, and thrombin-induced platelet aggregation

Question 3

Apixaban, edoxaban, and rivaroxaban

Answer 3

Reversible inhibitors of activated factor X (factor Xa) which prevents thrombin generation and thrombus development.

Question 4

INDICATIONS

Answer 4

• Prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation
• For the treatment and secondary prevention of DVT / PE

Question 5

Additional indication for Apixaban, dabigatran and rivaroxaban

Answer 5

Used for the prevention of venous thromboembolism after elective hip or knee replacement surgery

Question 6

An additional indication for Rivaroxaban

Answer 6

Used for the prevention of atherothrombotic events in patients with coronary or peripheral artery disease, and following an acute coronary syndrome with raised biomarkers in specific circumstances

Question 7

Hemorrhage

Reversal agents are available for dabigatran etexilate, apixaban, and rivaroxaban.

Answer 7

Idarucizumab is licensed for the rapid reversal of dabigatran etexilate in life-threatening or uncontrolled bleeding, or for emergency surgery or urgent procedures.

Andexanet alfa is licensed for the reversal of apixaban or rivaroxaban in life-threatening or uncontrolled bleeding.

Question 8

APIXABAN

DOSES FOR -
Prophylaxis of venous thromboembolism following knee + hip replacement surgery

Answer 8

KNEE REPLACEMENT :
2.5 mg twice daily for 10–14 days, to be started 12–24 hours after surgery.

HIP REPLACEMENT:
2.5 mg twice daily for 32–38 days, to be started 12–24 hours after surgery.

Question 9

Treatment of deep-vein thrombosis + Treatment of pulmonary embolism

Answer 9

Initially, 10 mg twice daily for 7 days, then maintenance 5 mg twice daily.

Question 10

Prophylaxis of recurrent deep-vein thrombosis + pulmonary embolism

Answer 10

2.5 mg twice daily, following completion of 6 months anticoagulant treatment.

Question 11

Prophylaxis of stroke and systemic embolism in non-valvular atrial fibrillation and at least one risk factor
(e.g. previous stroke or transient ischaemic attack, symptomatic heart failure, diabetes mellitus, hypertension, or age 75 years + )

What are 3 dose adjustment factors:

Answer 11

Normal dose: 5 mg twice daily, alternatively 2.5 mg twice daily,

The reduced dose was used in patients with at least two of the following characteristics:

1) Age 80 years and over
2) Body-weight 60 kg or less
3) Serum creatinine >133 micromol/liter or CrCl is 15–29 mL/minute.

Question 12

EDOXABAN

DOSE FOR - Prophylaxis of stroke and systemic embolism in non-valvular atrial fibrillation, in patients with at least one risk factor

Answer 12

Adult (body-weight up to 61 kg)
30 mg once daily.

Adult (body-weight 61 kg and above)
60 mg once daily.

Question 13

Treatment + prophylaxis of recurrent DVT OR PE

Answer 13

Adult (body-weight up to 61 kg)
30 mg once daily, duration of treatment adjusted according to risk factors—consult product literature, treatment should follow initial use of parenteral anticoagulant for at least 5 days.

Adult (body-weight 61 kg and above)
60 mg once daily, duration of treatment adjusted according to risk factors—consult product literature, treatment should follow initial use of parenteral anticoagulant for at least 5 days.

Question 14

Dose adjustments due to interactionsfor edoxaban

Answer 14

The manufacturer advises max. dose of 30 mg once daily with concurrent ciclosporin, dronedarone, erythromycin, or ketoconazole.

Avoid if creatinine clearance less than 15 mL/minute.

Dose adjustments:
Use a dose of 30 mg once daily if creatinine clearance 15–50 mL/minute

Question 15

RIVAROXABAN

Dose for Prophylaxis of VTE following KNEE OR HIP replacement surgery

Answer 15

KNEE REPLACEMENT - 10 mg once daily for 2 weeks, to be started 6–10 hours after surgery.

HIP REPLACEMENT - 10 mg once daily for 5 weeks, to be started 6–10 hours after surgery.

Question 16

Dose for Treatment of DVT + PE

Answer 16

Initially, 15 mg twice daily for 21 days, then maintenance 20 mg once daily, to be taken with food, for the duration of treatment

Following the first 21 days of treatment for deep-vein thrombosis or pulmonary embolism, the usual dose of 20 mg once daily can be given, but consider reducing to 15 mg once daily if creatinine clearance 15–49 mL/minute

Question 17

Prophylaxis of recurrent DVT OR PE

Answer 17

10 mg once daily, following completion of at least 6 months of anticoagulant treatment, to be taken with food, consider 20 mg once daily in those at high risk of recurrence (such as complicated comorbidities, or previous recurrence with rivaroxaban 10 mg once daily

Question 18

Prophylaxis of stroke and systemic embolism in patients with non-valvular atrial fibrillation and with at least one of the following risk factors: congestive heart failure, hypertension, previous stroke or transient ischaemic attack, age ≥ 75 years, or diabetes mellitus

Answer 18

20 mg once daily, to be taken with food.

Question 19

Prophylaxis of atherothrombotic events following an acute coronary syndrome with elevated cardiac biomarkers (in combination with aspirin alone or aspirin and clopidogrel)

Answer 19

2.5 mg twice daily usual duration 12 months

Question 20

MHRA ADVICE FOR RIVAROXABAN

Answer 20

MHRA/CHM advice: Rivaroxaban (Xarelto®): reminder that 15 mg and 20 mg tablets should be taken with food (July 2019)

The MHRA has received a small number of reports suggesting a lack of efficacy (thromboembolic events) in patients taking 15 mg or 20 mg rivaroxaban tablets on an empty stomach.

In those who have difficulty swallowing, these tablets can be crushed and mixed with water or apple puree immediately before, and followed by food immediately after, ingestion.

Question 21

DABIGATRAN

Prophylaxis of venous thromboembolism following total KNEE / HIP replacement surgery

Answer 21

Adult 18–74 years
110 mg, to be taken 1–4 hours after surgery, followed by 220 mg once daily for (10 days for knee or 28-35 days for hip) to be taken on the first day after surgery.

Adult 75 years and over
75 mg, to be taken 1–4 hours after surgery, followed by 150 mg once daily for (10 days for knee or 28-35 days for hip) to be taken on the first day after surgery.

Question 22

Prophylaxis of venous thromboembolism following total knee / hip replacement surgery in patients receiving concomitant treatment with amiodarone or verapamil
for dabigatran etexilate

Answer 22

Adult 18–74 years
75 mg, to be taken 1–4 hours after surgery, followed by 150 mg once daily for (10 days for knee or 28-35 days for hip) to be taken on the first day after surgery.

Adult 75 years and over
75 mg, to be taken 1–4 hours after surgery, followed by 150 mg once daily for (10 days for knee or 28-35 days for hip) to be taken on the first day after surgery.

Question 23

Treatment of deep-vein thrombosis,
Treatment of pulmonary embolism,
Prophylaxis of recurrent deep-vein thrombosis,
Prophylaxis of recurrent pulmonary embolism
for dabigatran etexilate

Answer 23

Adult 18–74 years
150 mg twice daily, following at least 5 days treatment with a parenteral anticoagulant.

Adult 75–79 years
110–150 mg twice daily, following at least 5 days treatment with a parenteral anticoagulant.

Adult 80 years and over
110 mg twice daily, following at least 5 days treatment with a parenteral anticoagulant.

Question 24

Prophylaxis of stroke and systemic embolism in non-valvular atrial fibrillation and with one or more risk factors such as previous stroke or transient ischaemic attack, symptomatic heart failure, age ≥ 75 years, diabetes mellitus, or hypertension

Answer 24

By mouth
Adult 18–74 years
150 mg twice daily.

Adult 75–79 years
110–150 mg twice daily.

Adult 80 years and over
110 mg twice daily.