Abstract: A lyophilized fibrinogen is produced which is subjected to a severe terminal virucidal heat treatment in order to inactivate viruses present, while retaining desirable biological properties. In particular the lyophilized fibrinogen has a solubility in water or other aqueous solution to 40 g/l in less than 20 minutes at 20.degree. C., and a clotting time of less than 10 seconds when exposed to at least 200 U/ml thrombin. The product may be heat treated at 80.degree. C. for 72 hours up to 100.degree. C. for 10 hours depending on formulation and water content. In the production process cryoprecipitate is washed with polyethylene glycol solution at 4 to 10.degree. C. and pH 6.8 to 8 at low ionic strength, prior to two-stage freeze drying.

Abstract: A peptide of formula:A--D--X--D--Mrp--B (I)A--D--X--D-.beta.Nal--B (II)E--D--X--Mrp--NH.sub.2 (III)wherein A is hydrogen, 2-aminoisobutyryl, or 4-aminobutyryl;D relates to the dextro isomer;X is Mrp, wherein Mrp is a 2-alkyltryptophan of formula (IV): ##STR1## wherein R is hydrogen, CHO, SO.sub.2 CH.sub.3, mesitylene-2-sulfonyl, PO.sub.3 (CH.sub.3).sub.2, PO.sub.3 H.sub.2, wherein R.sub.1 is a C.sub.1 -C.sub.3 alkyl group, or wherein X is a residue of protected serine, Ser (Y), wherein Y is benzyl, p-chlorobenzyl, 4-methoxybenzyl, 2,4,6-trimethoxybenzyl, or tert-butyl;B is NR.sub.2 R.sub.3, wherein R.sub.2 and R.sub.3, may be the same or different, are hydrogen, a C.sub.1 -C.sub.3 alkyl group, an OR.sub.4 group, wherein R.sub.4 is hydrogen, a C.sub.1 -C.sub.3 alkyl group or the C--Lys--NH.sub.2 group, wherein C is Phe, Mrp or D--Mrp;E is hydrogen, GAB or D--Mrp, and addition salts with pharmaceutically acceptable organic or inorganic acids of the peptide.