New carbohydrate-based anticoagulants devoid of the side effects of unfractionated heparin are currently under development and show a major potential for patients with heparin-induced thrombocytopenia (HIT) who still require efficient antithrombotic therapy. As HIT is usually associated with antibodies to heparin-platelet factor 4 (H-PF4) complexes, cross-reactivity of the heparin pentasaccharide SR90107A/ORG31540 was tested in the presence of PF4 with the plasma from 49 patients with HIT. No cross-reactivity was observed whatever the pentasaccharide concentrations. Although more extensive studies are required for excluding its total absence of immunogenicity and pathogenicity, this pentasaccharide is a candidate for use in emergency situations in patients with HIT.