Hemorrhage

The most commonly reported adverse reactions are hematoma at the injection site and hemorrhagic complications. The risk for bleeding varies with the indication and may increase with higher doses.

Hip Replacement Surgery

Table 8 summarizes: 1) all major bleeding reactions and, 2) other bleeding reactions possibly or probably related to treatment with FRAGMIN (preoperative dosing regimen), warfarin sodium, or heparin in two hip replacement surgery clinical trials.

Six of the patients treated with FRAGMIN experienced seven major bleeding reactions. Two of the reactions were wound hematoma (one requiring reoperation), three were bleeding from the operative site, one was intraoperative bleeding due to vessel damage, and one was gastrointestinal bleeding.

In the third hip replacement surgery clinical trial, the incidence of major bleeding reactions was similar in all three treatment groups: 3.6% (18/496) for patients who started FRAGMIN before surgery; 2.5% (12/487) for patients who started FRAGMIN after surgery; and 3.1% (15/489) for patients treated with warfarin sodium.

Abdominal Surgery

Table 9 summarizes bleeding reactions that occurred in clinical trials which studied FRAGMIN 2,500 units and 5,000 units administered once daily to abdominal surgery patients.

In a trial comparing FRAGMIN 5,000 units once daily to FRAGMIN 2,500 units once daily in patients undergoing surgery for malignancy, the incidence of bleeding reactions was 4.6% and 3.6%, respectively (n.s.). In a trial comparing FRAGMIN 5,000 units once daily to heparin 5,000 units twice daily, in the malignancy subgroup the incidence of bleeding reactions was 3.2% and 2.7%, respectively for FRAGMIN and Heparin (n.s.).

Adult Patients with Cancer and Acute Symptomatic VTE

Table 11 summarizes the number of patients with bleeding reactions that occurred in the clinical trial of adult patients with cancer and acute symptomatic VTE. A bleeding event was considered major if it: 1) was accompanied by a decrease in hemoglobin of ≥2 g/dL in connection with clinical symptoms; 2) occurred at a critical site (intraocular, spinal/epidural, intracranial, retroperitoneal, or pericardial bleeding); 3) required transfusion of ≥2 units of blood products; or 4) led to death. Minor bleeding was classified as clinically overt bleeding that did not meet criteria for major bleeding.

At the end of the six-month study, a total of 46 (13.6%) patients in the FRAGMIN arm and 62 (18.5%) patients in the OAC arm experienced any bleeding event. One bleeding event (hemoptysis in a patient in the FRAGMIN arm at Day 71) was fatal.

Elevations of Serum Transaminases

In FRAGMIN clinical trials supporting non-cancer indications, where hepatic transaminases were measured, asymptomatic increases in transaminase levels (SGOT/AST and SGPT/ALT) greater than three times the upper limit of normal of the laboratory reference range were seen in 4.7% and 4.2%, respectively, of patients during treatment with FRAGMIN.

In the FRAGMIN clinical trial of patients with cancer and acute symptomatic venous thromboembolism treated with FRAGMIN for up to 6 months, asymptomatic increases in transaminase levels, AST and ALT, greater than three times the upper limit of normal of the laboratory reference range were reported in 8.9% and 9.5% of patients, respectively. The frequencies of Grades 3 and 4 increases in AST and ALT, as classified by the National Cancer Institute, Common Toxicity Criteria (NCI-CTC) Scoring System, were 3% and 3.8%, respectively. Grades 2, 3 & 4 combined have been reported in 12% and 14% of patients, respectively.

Other

Pediatric Patients with Symptomatic VTE

The data below reflect exposure to FRAGMIN from two studies in pediatric patients from newborn to less than 18 years of age with or without cancer and symptomatic VTE (n = 50). Patients were started on FRAGMIN using age and weight-based dosing via subcutaneous injection twice daily. Anti-Xa levels were measured prior to the 4th dose and then periodically to determine whether dose adjustments were required, using 25 units/kg increments, to achieve a target anti-Xa level of 0.5 units/mL to 1.0 units/mL. The median time on treatment with FRAGMIN was 86 days (range 2 days to 170 days).

In pediatric patients with symptomatic VTE, the most common (greater than 10%) adverse reactions were injection site bruising (30%), contusion (12%), and epistaxis (10%).

Major bleeding was defined as any fatal bleeding, clinically overt bleeding with a decrease in hemoglobin of ≥2g/dL in 24 hours, overt bleeding deemed by the attending physician to be unrelated to the subject's underlying condition and accompanied by blood product administration, overt bleeding that was retroperitoneal, intracranial, intraspinal, intraocular, or intraarticular, or overt bleeding deemed by the attending physician to necessitate permanent discontinuation of trial medication. Major bleeding (intestinal hematoma) occurred in one patient (2%). Discontinuation due to adverse reactions occurred in 12% of patients, most often due to thrombocytopenia (4%).

Neonatal Patients

No controlled clinical trials have been conducted with FRAGMIN in neonatal patients with VTE; however, data are available from a non‑interventional retrospective medical chart review study of 16 neonates with VTE in the UK who were admitted to hospital between January 2010 and December 2021 and were treated with FRAGMIN. The mean (±SD) duration of dalteparin treatment was 62±30 days. For these 16 neonatal patients, the mean (±SD) daily dose of dalteparin at initiation was 365±196 units/kg (median:309 units/kg). The mean (±SD) daily dose of dalteparin including dose at initiation and dose changes was 575±320 units/kg (median: 450 units/kg). After the initial dose, all patients required one or more dose changes; 15 of 16 patients required dose increases due to anti-Xa level being initially below the target range of 0.5 units/mL to 1 units/mL.

The safety profile in neonates was similar to other pediatric patients.