Crystalline form of triethylenetetramine tetrahydrochloride and its pharmaceutical use
The present invention describes a new crystalline form of triethylenetetramine tetrachloride which has improved room temperature stability over known forms and over the dichloride salt. The new crystalline form is characterised by having peaks in an XRPD spectrum at 22.9, 25.4, 25.8, 26.6, 34.6 and 35.3±0.1°2θ and Raman shifts 943, 1173, 1527 and 1612±5 cm −1 . The crystalline form of triethylenetetramine tetrachloride is useful in the treatment of Wilson's disease.
1. A crystalline form of triethylenetetramine tetrahydrochloride Form B having at least one of the following characteristics:
(i) an XRPD pattern having at least two peaks selected from the peaks at 22.9, 25.4, 25.8, 26.6, 34.6 and 35.3±0.1°2θ; and
(ii) a Raman spectrum having at least two peaks selected from the peaks at a Raman shift of 943, 1173, 1527 and 1612±5 cm −1 ;
wherein the crystalline form contains no more than 10 wt % of triethylenetetramine tetrahydrochloride Form A having an XRPD pattern having peaks at 25.2 and 35.7±0.1°2θ; and
XRPD pattern peaks are as measured using a wavelength of 1.5418 Å.
2. The crystalline form according to claim 1 , having an XRPD pattern having peaks at 25.4, 34.6 and 35.3±0.1°2θ.
3. The crystalline form according to claim 1 , which contains at least 95 wt % of triethylenetetramine tetrahydrochloride Form B having:
(i) an XRPD pattern as defined in claim 1 ; and/or
(ii) a Raman spectrum having at least two peaks selected from the peaks at a Raman shift of 943, 1173, 1527 and 1612±5 cm −1 .
4. A pharmaceutical composition comprising the crystalline form according to claim 1 and a pharmaceutically acceptable carrier or diluent.
5. The pharmaceutical composition according to claim 4 , which contains no more than 5 wt % triethylenetetramine tetrahydrochloride Form A having an XRPD pattern having peaks at 25.2 and 35.7±0.1°2θ.
6. The pharmaceutical composition according to claim 5 , which contains no more than 2 wt % triethylenetetramine tetrahydrochloride Form A having an XRPD pattern having peaks at 25.2 and 35.7±0.1°2θ.
7. The pharmaceutical composition according to claim 5 which contains no more than 1 wt % triethylenetetramine tetrahydrochloride Form A having an XRPD pattern having peaks at 25.2 and 35.7±0.1°2θ.
8. A solid oral dosage composition comprising the crystalline form according to claim 1 and a pharmaceutically acceptable carrier.
9. A solid oral dosage composition comprising the crystalline form according to claim 2 and a pharmaceutically acceptable carrier.
10. A solid oral dosage composition comprising the crystalline form according to claim 3 and a pharmaceutically acceptable carrier.