Efficacy and safety of aceclofenac and drotaverine fixed-dose combination in the treatment of primary dysmenorrhoea: a double-blind, double-dummy, randomized comparative study with aceclofenac.

OBJECTIVE: To evaluate the efficacy and safety of aceclofenac-drotaverine combination against aceclofenac alone in patients with primary dysmenorrhoea. STUDY DESIGN: This double-blind, double-dummy, randomized, comparative, multicentric study enrolled 200 women (100 women in each arm) in the age range of 18-35 years with primary dysmenorrhoea at four centers. The patients were randomly allocated to either aceclofenac 100mg-drotaverine 80 mg b.i.d or aceclofenac 100mg alone b.i.d for a maximum of 3 days. Primary efficacy parameters were total area under pain relief (PR) score up to 4 and 8h (TOPAR/4 and TOPAR/8). Secondary efficacy measurements were pain-intensity difference (PID), sum of PID over 4 and 8h (SPID/4 and SPID/8), peak PID over 4 and 8h and peak PR over 4 and 8h, total study drug consumption, and patient's and investigator's global evaluation of the efficacy. RESULTS: Both treatments showed significant improvement in baseline values in all efficacy parameters. The combination was significantly superior to monotherapy in terms of TOPAR/4 (24.0 vs 18.54) (p=0.000) and TOPAR/8 (40.3 vs 35.2) (p=0.003), SPID/4 (-17.9 vs -13.88) (p=0.000) and SPID/8 (-31.06 vs -26.8) (p=0.001), peak PID/4 (-6.60 vs -5.75) (p=0.001) and peak PR/4 (8.26 vs 7.10) (p=0.000). At the end of 8h, both treatments were comparable with respect to peak PID/8 and peak PR/8 (p>0.05). The total number of doses consumed by patients treated with combination therapy was less than with monotherapy (150 vs 168 doses). The combination was significantly superior to monotherapy with respect to patient's and investigator's global evaluation of the efficacy (p=0.002 and p=0.001, respectively). Both treatments were well tolerated. CONCLUSION: This study establishes the efficacy of aceclofenac-drotaverine combination in patients with primary dysmenorrhoea. The fixed-dose combination of aceclofenac and drotaverine should therefore be considered as a suitable, effective and well tolerated treatment option for primary dysmenorrhoea.

Calcium binding properties of gamma-crystallin: calcium ion binds at the Greek key beta gamma-crystallin fold.

The beta- and gamma-crystallins are closely related lens proteins that are members of the betagamma-crystallin superfamily, which also include many non-lens members. Although beta-crystallin is known to be a calcium-binding protein, this property has not been reported in gamma-crystallin. We have studied the calcium binding properties of gamma-crystallin, and we show that it binds 4 mol eq of calcium with a dissociation constant of 90 microm. It also binds the calcium-mimic spectral probes, terbium and Stains-all. Calcium binding does not significantly influence protein secondary and tertiary structures. We present evidence that the Greek key crystallin fold is the site for calcium ion binding in gamma-crystallin. Peptides corresponding to Greek key motif of gamma-crystallin (42 residues) and their mutants were synthesized and studied for calcium binding. These peptides adopt beta-sheet conformation and form aggregates producing beta-sandwich. Our results with peptides show that, in Greek key motif, the amino acid adjacent to the conserved aromatic corner in the "a" strand and three amino acids of the "d" strand participate in calcium binding. We suggest that the betagamma superfamily represents a novel class of calcium-binding proteins with the Greek key betagamma-crystallin fold as potential calcium-binding sites. These results are of significance in understanding the mechanism of calcium homeostasis in the lens.