Background Protease inhibitor-based triple therapy increases the expected incidence and severity of haematological adverse events, with repercussions on the total cost.

Purpose To assess the incidence, management and incremental cost of thrombocytopenia in chronic hepatitis C virus (HCV) patients treated during the first 12 weeks with telaprevir/boceprevir-based triple therapy.

Material and methods Retrospective observational study conducted (June 2012–February 2013) at the outpatients department of a general hospital. HCV genotype-1 patients were included treated with telaprevir (750 mg/8 h) or boceprevir (400 mg/8 h), ribavirin (1,000–1,200 mg/day) and Peg-IFN-α2a (180 μg/week) or Peg-IFN-α2b (1.5 μg/kg/week). Patients were monitored during the first 12 week of treatment. Their medical records were reviewed for platelet count at baseline, week 4 and 12 from the start of triple therapy. Thrombocytopenia was categorised according to degree of toxicity and magnitude of change. Additional procedures due to thrombocytopenia (clinical appointments, laboratory tests, drugs and platelet concentrates) were recorded and costed.

Results 53 patients were included: 32 men, 51 ± 10years-old, 73 ± 7kg. 36 patients were treated with telaprevir and 17 with boceprevir. Platelet counts were 107.7 ± 59.1 × 10⁹/L at week 4 and 104.2 ± 64.4 × 10⁹/L at week 12. No significant differences were found in the magnitude of change at week 4 (-44 × 10⁹/L (95% CI: -99 × 10⁹/L to 10 × 10⁹/L)) and 12 (-48 × 10⁹/L (95% CI: -106 × 10⁹/L to 10 × 10⁹/L)). Table 1 shows the degree of thrombocytopenia. 42 patients experienced thrombocytopenia. In these, 130 medical visits were involved, 13 emergency room visits, 2 days of hospitalisation, 165 blood tests and 2 treatments with eltrombopag. The incremental cost was 12,709 euros (240 euros/patient). Increased costs of 156 euros/patient were estimated with thrombocytopenia grades I-II and 566 euros/patient with grades III-IV.

Conclusion Patients with telaprevir/boceprevir-based triple therapy experience a high incidence of thrombocytopenia during the first 12 weeks, with significant impacts on overall cost, especially for grades III–IV. The cost of adverse events should be taken into account when considering the financial burden of the disease.

References and/or acknowledgements No conflict of interest.