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Background Sunitinib and sorafenib can induce serious adverse drug reactions (ADR) such as hypothyroidism. However, the incidence has not been reliably determined in clinical trials. Aims To determine incidence rates (IR) and hazard ratios (HR) of thyroid hormone (TH) therapy as a surrogate for sunitinib- and sorafenib-induced clinical hypothyroidism. Methods A cohort study was performed using claims data for prescriptions covering >80% of German pharmacies. Patients with a first prescription of sunitinib or sorafenib in the period between June 2006 and December 2007 were followed until incident prescription of any TH (event of interest) or censoring (due to loss to follow-up, discontinuation or switch of therapy, prescription of antithyroid drugs or the end of the study). Results One-hundred and seventy eight of 1295 sunitinib patients (13.7%) versus 77 of 1214 sorafenib patients (6.3%) received a TH. IR were 24.2 and 12.1 per 100 person-years, respectively. Unadjusted HR for TH therapy was 2.0 (95% confidence interval (CI) 1.5–2.6) for sunitinib compared to sorafenib and remained significant after adjustment for covariates, i.e. type of prescriber, region, insurance status, type of insurance fund, and relevant co-medication. Conclusions Sunitinib- and sorafenib-induced hypothyroidism is a more frequent ADR than currently labelled. Furthermore, patients treated with sunitinib have a two-fold increased risk of requiring TH therapy compared to sorafenib. Patients being treated with sunitinib or sorafenib are, therefore, at risk of thyroid function disturbances and routine monitoring both at baseline and throughout treatment with sunitinib and sorafenib is justified.

Pyridoxal-5'-phosphate-6-(2'-naphthylazo-6'-nitro-4',8'-disulfonat e) (PPNDS) potently antagonized P2X(1) receptor-mediated responses in rat vas deferens (pK(B)=7.43) and Xenopus laevis oocytes (pIC(50)=7. 84). It showed lower (up to 20,000-fold) inhibitory potency on ecto-nucleotidase in Xenopus oocytes and on P2Y(1) receptors in guinea-pig ileum (pA(2)=6.13). PPNDS did not interact with alpha(1A)-adrenoceptors, adenosine A(1) and A(2B), histamine H(1) and muscarinic M(3) receptors. Thus, PPNDS is a novel, specific P2 receptor antagonist and represents the pyridoxal-5'-phosphate derivative with the highest potency at P2X(1) receptors.

Among suramin analogues, the properties of P2 receptor subtype blockade and ecto-nucleotidase inhibition appear to be controlled by different structural parameters (Fig. 1 and 2, Table 1; Van Rhee et al., 1994; Beukers et al., 1995; Bultmann et al., 1996; Damer et al., 1998a, 1998b; and this study): the molecular size of the compounds, the position of the sulfonic acid residues in the naphthalene rings, the substitution pattern of the benzoyl moieties and the 3'- or 4'-aminobenzoyl-linkages of the phenyl rings "1" and "2". As a result, compounds with different receptor selectivity profiles were obtained. A maximum in potency at and selectivity for P2X1 receptors is reached in NF279, which is a specific P2 receptor antagonist and the compound with the highest P2X1 vs. P2Y receptor and ecto-nucleotidase selectivity presently available.

8,8'-(Carbonylbis(imino-4, 1 -phenylenecarbonylimino-4,1-phenylenecarbonylimino))bis(1,3, 5-naphthalenetrisulfonic acid) (NF279) antagonized P2X receptor-mediated contractions in rat vas deferens, evoked by alpha,beta-methylene ATP (10 microM; pIC50=5.71) without affecting responses mediated via alpha1A-adrenoceptors, adenosine A1 and A2B receptors, histamine H1, muscarinic M3 and nicotinic receptors. The low inhibitory potency of NF279 on P2Y receptors in guinea-pig taenia coli (pA2=4.10) and at ecto-nucleotidases in folliculated Xenopus laevis oocytes (IC50 > 100 microM) indicates that NF279 is a novel specific and selective P2X receptor antagonist.

Background Ginkgo biloba drugs (Gb) are reimbursed within the German statutory health insurance (SHI) scheme for treatment of dementia. In 2008, a novel Gb product containing 240 mg Ginkgo extract EGb761® per tablet was introduced aiming to facilitate medication use by incorporating the recommended daily dose in one single tablet. The aim of this study was to evaluate the relationship between dosage strength and persistence in a representative population of patients treated with Gb. Methods Retrospective cohort study in ambulatory drug claims database within the German SHI system. Persistence was defined as continuous treatment with an allowable gap of 20% between refills. Multivariate regression models were conducted to identify variables associated with persistence. Results Among 13,810 patients initiating treatment with Gb in 2008, 430 (3.1%) received a dosage strength of 240 mg, 7,070 (51.2%) a dosage strength of 120 mg and 6,310 (45.7%) dosage strengths containing less than 120 mg Gb per tablet. After 6 months, persistence was highest for patients treated with the 240 mg dosage form (22.8% of patients), although persistence was low in general (5.7% and 0% of patients treated with 120 mg and less than 120 mg, respectively). Risk for non-persistence was reduced in patients receiving 240 mg products compared to 120 mg (HR = 0.63; 95%CI 0.57 – 0.70). Conclusions Patients initially treated with Gb 240 mg were more persistent compared to those receiving lower dosage strengths. Nevertheless, persistence with Gb therapy is generally low and should be improved in order to better realize therapeutic effects.