Successful Long-term Anticoagulation with Enoxaparin in a Patient with a Mechanical Heart Valve

Thromboembolism related to a mechanical heart valve (MHV) is a major complication after surgical valve replacement. Warfarin remains as guideline-endorsed thromboprophylaxis in patients with MHVs. Alternative anticoagulation therapy for patients who do not tolerate or who fail warfarin is not adequately covered in the current guidelines. We report a case of successful long-term anticoagulation with enoxaparin in a patient with a mechanical aortic valve who had a contraindication to warfarin. The patient developed a left thigh hematoma requiring surgical evacuation 1 month after initiation of weight-based dosing of enoxaparin. His dose was then titrated based on peak anti-factor Xa levels (goal 0.6-1.0 IU/ml). He remained free of signs and symptoms of thromboembolic events, valve dysfunction, bleeding complications, or major adverse effects from long-term enoxaparin use for the next 13 years. Our case provides promising evidence of the potential role of enoxaparin in patients with MHVs in whom warfarin thromboprophylaxis is not possible. Meticulous monitoring of anti-factor Xa levels and dosage adjustments are crucial to treatment success.

Randomized Phase 2 Trial of Pharmacodynamic Separation of Pemetrexed and Intercalated Erlotinib Versus Pemetrexed Alone for Advanced Nonsquamous, Non-small-cell Lung Cancer

BACKGROUND

Pharmacodynamic separation of pemetrexed and erlotinib avoids negative cellular interactions and results in antitumor synergy in erlotinib-resistant non-small-cell lung cancer (NSCLC) cells, independent of EGFR (epidermal growth factor receptor) genotype.

PATIENTS AND METHODS

Patients with platinum-treated metastatic nonsquamous NSCLC were randomly assigned 1:2 to pemetrexed alone (500 mg/m² provided intravenously on day 1) or pemetrexed followed by erlotinib (150 mg provided orally once daily on days 2-17) every 21 days. EGFR genotype was centrally confirmed by Sequenom multiplex oncogenotyping assay. The primary end point was progression-free survival (PFS), which would be considered promising for future study if median PFS was ≥ 4.5 months.

RESULTS

Of 83 patients enrolled, 79 were randomized to either pemetrexed alone (n = 27) or in combination (n = 52). Fifty-nine (79%) of 75 eligible patients had tumors with confirmed EGFR genotype: 7 with activating mutations and 52 wild type. Median PFS was 4.7 and 2.9 months in the combination and pemetrexed-alone groups, respectively. In patients with EGFR wild-type tumors, median PFS was 5.3 and 3.5 months in the combination and pemetrexed-alone groups, respectively. Objective response rate (29% vs. 10%, P = .17), 6-month PFS (45% vs. 29%, P = .26), and 12-month PFS (23% vs. 10%, P = .28) were all higher in the combination arm. Rash (67% vs. 26%, P = .0007) and diarrhea (44% vs. 11%, P = .003) were significantly more common in the combination arm.

CONCLUSION

In patients with unselected or EGFR wild-type advanced nonsquamous NSCLC, pharmacodynamic separation of pemetrexed and intercalated erlotinib had promising antitumor activity without new safety concerns. The combination merits further evaluation as maintenance or second-line therapy against new standards in patients with EGFR wild-type advanced NSCLC.

CA19-9 decrease at 8 weeks as a predictor of overall survival in a randomized phase III trial (MPACT) of weekly nab-paclitaxel plus gemcitabine versus gemcitabine alone in patients with metastatic pancreatic cancer

Any CA19-9 decline at week 8 and radiologic response by week 8 each predicted longer OS in both treatment arms. In the nab-P + Gem arm, the higher proportion of patients with week 8 CA19-9 decrease [82% (206/252); median OS 13.2 months] than a RECIST-defined response [16% (40/252); median OS 13.7 months] suggests that CA19-9 decline is a predictor of OS applicable to a larger population.

Background

A phase I/II study and subsequent phase III study (MPACT) reported significant correlations between CA19-9 decreases and prolonged overall survival (OS) with nab-paclitaxel plus gemcitabine (nab-P + Gem) treatment for metastatic pancreatic cancer (MPC). CA19-9 changes at week 8 and potential associations with efficacy were investigated as part of an exploratory analysis in the MPACT trial.

Patients and methods

Untreated patients with MPC (N = 861) received nab-P + Gem or Gem alone. CA19-9 was evaluated at baseline and every 8 weeks.

Results

Patients with baseline and week-8 CA19-9 measurements were analyzed (nab-P + Gem: 252; Gem: 202). In an analysis pooling the treatments, patients with any CA19-9 decline (80%) versus those without (20%) had improved OS (median 11.1 versus 8.0 months; P = 0.005). In the nab-P + Gem arm, patients with (n = 206) versus without (n = 46) any CA19-9 decrease at week 8 had a confirmed overall response rate (ORR) of 40% versus 13%, and a median OS of 13.2 versus 8.3 months (P = 0.001), respectively. In the Gem-alone arm, patients with (n = 159) versus without (n = 43) CA19-9 decrease at week 8 had a confirmed ORR of 15% versus 5%, and a median OS of 9.4 versus 7.1 months (P = 0.404), respectively. In the nab-P + Gem and Gem-alone arms, by week 8, 16% (40/252) and 6% (13/202) of patients, respectively, had an unconfirmed radiologic response (median OS 13.7 and 14.7 months, respectively), and 79% and 84% of patients, respectively, had stable disease (SD) (median OS 11.1 and 9 months, respectively). Patients with SD and any CA19-9 decrease (158/199 and 133/170) had a median OS of 13.2 and 9.4 months, respectively.

Conclusion

This analysis demonstrated that, in patients with MPC, any CA19-9 decrease at week 8 can be an early marker for chemotherapy efficacy, including in those patients with SD. CA19-9 decrease identified more patients with survival benefit than radiologic response by week 8.