Treatment of atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in the world. Risk factor modification, anticoagulation, rhythm control, and rate control are the four pillars of its management. American College of Cardiology/American Heart Association (ACC/AHA) guidelines on management of AF were updated recently.

Prospective randomized trial of antithrombotic strategies following great saphenous vein ablation using injectable polidocanol endovenous microfoam (Varithena)

OBJECTIVE

Postablation deep vein thrombosis (DVT) represents a potentially serious complication after Varithena polidocanol endovenous microfoam (PEM) ablation. The following primary outcomes were assessed: whether (1) adjunctive apixaban anticoagulation or (2) mechanical deep venous system (DVS) saline flushing could decrease saphenofemoral junction (SFJ) thrombus extension (postablation superficial thrombus extension [PASTE]) and/or DVT compared with compression alone, after great saphenous vein (GSV) PEM ablation.

METHODS

Varithena 1% PEM ablation patients were randomized to (1) SFJ compression, (2) compression and DVS saline flushing, or (3) compression, DVS saline flushing, and 5 days of postprocedural 5 mg oral apixaban anticoagulation twice daily. Duplex imaging was obtained 7 to 10 days after PEM ablation and PASTE/DVT incidence (primary end point) was compared between groups at this time point.

RESULTS

We treated 304 limbs in 257 patients with PEM. Overall, 103 limbs received SFJ compression (group C, 33.8%), 101 received compression and deep venous flushing (group D, 32.9%), and 100 received compression, deep flush, and anticoagulation (group A, 33.2%). Mean ultrasound follow-up time was 9.7 days (all patients) with a primary GSV closure rate of 92.4%. SFJ PASTE (II-IV) occurred in 0.9%, 1.0%, and 0% (groups C, D, and A, respectively). DVT occurred in 16.7%, 14.7%, and 1.98% (groups C, D, and A; χ², P = .002). Patients in group A receiving apixaban anticoagulation had a significant reduction in DVT compared with patients in group C (1.98% vs 16.7%, χ²; P < .001); likewise, patients in group A had a significantly decreased DVT occurrence compared with group D (14.7% vs 1.98%; χ², P = .00162), whereas patients in groups C and D were not statistically different (16.7% vs 14.7%; χ², P = .60).

CONCLUSIONS

(1) Neither adjunctive DVS flushing nor anticoagulation decreased clinically relevant SFJ PASTE (II-IV) incidence, which remained similarly low across all groups and ranged between 0% and 1%, regardless of adjunctive DVS flushing or anticoagulation. This rate was significantly lower than prior reports (2.3%-4.1%). (2) DVS flushing had no influence on the rate of DVT. Observed PEM-induced DVT incidence using SFJ compression alone or compression with DVS flushing (16.7% and 14.7%, respectively) was significantly higher than prior reports (2.5%-9.6%). This finding may relate to the greater extent of AK/BK GSV territory treated in the present study. (3) Five days of postprocedural oral apixaban anticoagulation, 5 mg given twice daily, significantly decreased DVT occurrence to 1.98%, compared with nonanticoagulated patients (16.7%). This finding is comparable with the DVT rates reported after endovenous thermal ablation (0.7-1.7%). (4) Postprocedural apixaban anticoagulation may have a significant preventive role in decreasing DVT occurrence after PEM ablation.

The Safety and Efficacy of Apixaban (Eliquis) in 5017 Post-bariatric Patients with 95.3% Follow-up: a Multicenter Study

BACKGROUND

Thromboprophylaxis in bariatric surgery is widely debated; however, few large articles evaluate treatment plans and their efficacy. Herein, we make the first large-scale report of the safety and efficacy of apixaban (Eliquis) for thrombus prevention following bariatric surgery.

PURPOSE

To evaluate the safety and efficacy of apixaban following bariatric surgery.

SETTING

Three private institutes, USA.

MATERIALS AND METHODS

Data from 5017 consecutive bariatric patients that were placed on postoperative apixaban for thromboprophylaxis were used for retrospective analysis. The dose prescribed to patients was 2.5 mg PO BID for a total of 30 days starting on day 3 postoperatively.

RESULTS

In total, of the 5017 patients, 59.7%, 31.2%, 4.4%, 2.5%, 1.8%, and 0.1% of the patients had undergone sleeve gastrectomy (SG), single-anastomosis duodeno-ileal bypass with SG (SADI-S), Roux-en-Y gastric bypass (RYGB), conversion from SG to SADI, small bowel reconstruction, and RYGB reversal, respectively. The 30-day follow-up rate was 95.3%. In total, 1.7% of patients experienced apixaban-related side effects. The most common side effects were menorrhagia and rash. Two (0.03%) side effects developed into Clavien-Dindo grade II complications. Overall, 10 (0.1%) patients experienced thromboembolic complications (five (0.09%) PVTs and five (0.09%) PEs). In each case, the protocol was not followed for extenuating circumstances. There were no deaths or thromboembolic events in cases where the protocol was able to be fully followed.

CONCLUSIONS

In conclusion, 30 days of postoperative apixaban appears to be safe and effective with minimal side effects while preventing thromboembolic events.

From basic science to life-saving therapy: the rationale, and drug discovery efforts that led to the direct factor Xa inhibitor eliquis

Over the past few decades, drug discovery directed at the treatment and prevention of thromboembolic diseases has been challenged by the need to balance robust efficacy with improved safety relative to the standard of care. To this end, the most impactful advance to date has been the discovery and development of oral factor Xa inhibitors. In this essay, a brief account of the program that culminated in the discovery of Eliquis (apixaban) and the commitment to identify a compound with an optimal profile are described.

Ovarian stimulation for fertility preservation in an oncology patient with etonogestrel implant in place

PURPOSE

To describe a case of a young woman who presented for fertility preservation and underwent ovarian stimulation with an etonogestrel implant in place.

METHODS

A 24-year old, gravida 0, with an etonogestrel implant and newly diagnosed lower extremity sarcoma and DVT desiring oocyte cryopreservation prior to adjuvant chemotherapy and radiation. To avoid delay in her oncologic care and allow for continued use of contraception post-retrieval, the patient underwent controlled ovarian hyperstimulation (COH) without removal of the etonogestrel implant.

RESULTS

Baseline labs included follicle-stimulating hormone 9 mIU/mL, luteinizing hormone 4.9 mIU/mL, estradiol 42 pg/mL, anti-Müllerian hormone 5.1 ng/mL, and antral follicle count greater than 40. The patient was placed on an antagonist protocol and stimulated with 125 IU Gonal-F and 75 IU Menopur. She received a total of 12 days of gonadotropin stimulation. On the day of trigger, her estradiol was 1472 pg/mL, lead follicle 21.5 mm with a total of 25 follicles measured > 12 mm. She was triggered with 5000 U hCG. She had a total of 23 oocytes retrieved, 17 of which were metaphase II and vitrified.

CONCLUSIONS

COH and successful oocyte cryopreservation can be achieved in patients with an etonogestrel implant in situ without apparent detrimental effects to oocyte yield or maturity. Due to the etonogestrel implant's inhibitory effects on LH, it is recommended to use an hCG trigger for final oocyte maturation.

Andexanet alfa for reversal of factor Xa inhibitor-associated anticoagulation

Background:

Review of clinical data on andexanet alfa for the reversal of factor Xa (FXa) inhibitor associated anticoagulation.

Data sources:

In the present review, we identified articles via PubMed using the combined keywords andexanet alfa, apixaban, enoxaparin, edoxaban, and rivaroxaban. Additional online searches via PubMed, Google Scholar, and Lexicomp were conducted for both prescribing and cost information. Portola Pharmaceuticals was contacted for information used for United States Food and Drug Administration approval of andexanet alfa.

Study selection and data extraction:

English-language clinical trials and reviews published between January 2008 and April 2019 were included for review. Bibliographies of selected articles were reviewed manually for relevant publications, focusing on reversal strategies for apixaban, enoxaparin, edoxaban, or rivaroxaban associated anticoagulation using andexanet alfa. Review articles were excluded.

Data synthesis:

The safety and tolerability of andexanet alfa were evaluated in one phase I, two phase II, and one phase III clinical trials. The use of andexanet alfa for reversing FXa inhibitor-associated anticoagulation were evaluated in the phase III ANNEXA-4 study.

Conclusions:

Studies evaluating laboratory parameters for coagulation show that andexanet alfa rapidly neutralizes the anticoagulant effects of apixaban, enoxaparin, edoxaban, and rivaroxaban. Clinical studies show that andexanet alfa improves markers related to coagulation, and reverses major bleeding in healthy volunteers and patients with life-threatening bleeding. Interruption of anticoagulation may result in thromboembolic and ischemic events. The use of andexanet alfa requires close monitoring for signs and symptoms of thromboembolic events, ischemic events, and cardiac arrest. Furthermore, anticoagulation should be resumed following the administration of andexanet alfa as soon as medically appropriate.

Evaluation of the single-dose pharmacokinetics and pharmacodynamics of apixaban in healthy Japanese and Caucasian subjects

Purpose

This double-blind, placebo-controlled, intra-subject, dose-escalation study assessed single-dose safety, pharmacokinetics, and pharmacodynamics of apixaban in healthy Japanese and Caucasian subjects.

Subjects and methods

Sixteen healthy male Japanese and sixteen healthy male Caucasian subjects, matched for age, weight, and smoking status were randomized to receive four sequential single oral doses of either apixaban (2.5, 10, 25, and 50 mg) or matched placebo. Doses were separated by a ≥5-day washout. Blood samples were collected for the determination of apixaban plasma concentration, clotting times (international normalized ratio [INR], activated partial thromboplastin time, and modified prothrombin time [mPT]), and ex vivo thrombin generation (TG). Urine samples were collected for the analysis of apixaban concentration.

Results

Ascending single doses of apixaban 2.5–50 mg were safe and well tolerated by all subjects. Apixaban exposure increased the dose proportionally up to 10 mg. Apixaban reached maximum concentrations (C_max) 3–4 h postdose, with mean C_max ranging from 52.5–485.0 to 44.8–494.3 ng/mL in Japanese and Caucasian subjects. The mean half-life was ~8 and ~13 h and the renal clearance was 1.1 and 0.8 L/h in Japanese and Caucasian subjects, respectively. Pharmacodynamic assessments were similar between ethnic groups, with comparable dose-related prolongation of INR and mPT and inhibition of TG.

Conclusion

Ascending single doses of apixaban over a 20-fold dose range were safe and well tolerated in Japanese and Caucasian subjects in this study. The consistency between pharmacokinetic and pharmacodynamic measures in Japanese and Caucasian subjects indicates that apixaban may be administered as a fixed dose with no need for adjustment in Japanese patients.