Abstract: Cyclic peptide of formula (1) where Xaa1 is selected from L-amino acids selected from Phe, Lys and Arg, D-amino acids selected from Phe and Met, the L- and D-amino acid optionally substituted on its &agr;-carbon or its &agr;-amino group with a C1-4 alkyl group; and Melle; Xaa2, Xaa3 et Xaa4 are respectively Leu, Asp and Val, optionally substituted on their &agr;-carbon or &agr;-amino group with a C1-4 alkyl group; X1 is selected from D-amino acids selected from Ala, Phe, Arg, Lys, Trp, hArg(Et)2, Orn(CHMe2), Orn(Me2), Lys(CHMe2) and Arg(Pmc), optionally substituted on their &agr;-carbon or &agr;-amino group with a C1-4 alkyl group; Formula (II); NH(CH2)5CO; and NH(CH2)2S(CH2)yCO, where y is 1 or 2; X2 is selected from D-amino acids selected from Ala, Arg, Lys, His, hArg(Et)2, Orm(CHMe2), and Om(Me2), optionally substituted on their &agr;-carbon or &agr;-amino group with a C1-4 alkyl group; NH(CH2)SCH2CO; and NH(CH2)xCO, where x is 2 or 3; Xaa5 and Xaa6 are each independently a

Abstract: Cyclic dimeric peptides of formula (I) ##STR1## wherein: peptide 1 and peptide 2 independently represent a tetrapeptide of formula -AA1-AA2-AA3-AA4- juxtaposed in parallel or antiparallel orientation; AA1 is an L or D amino acid selected from Ile, Leu and amino analogues thereof selected from Pro, Gly, Tic and Phe; AA2 is an L amino acid selected from Leu and amino acid analogues thereof selected from Ile, Phe and Val; AA3 is an L amino acid selected from Asp, Glu and amino acid analogues thereof; AA4 is an L amino acid selected from Val and amino acid analogues thereof selected from Leu, Ile, Phe and Cha (cyclohexylalanine); L1 and L2 independently represent linking moieties for linking peptides 1 and 2 to form a cyclic dipeptide; or salts thereof. The cyclic dipeptides inhibit the interaction of vascular cell adhesion molecule-1 and fibronectin with integrin very late antigen 4 and have therapeutic applications such as in rheumatoid arthritis, asthma or multiple sclerosis.

Abstract: Cyclic peptides of formula (1): ##STR1## Wherein: AA1 is an L or D amino acid selected from Ile and Leu or amino acid analogue thereof; AA2 is an L amino acid selected from Leu or amino acids analogue thereof; AA3 is an L amino acid selected from Asp or amino acid analogue thereof containing a carboxy group in its side chain; AA4 is an L amino acid selected from Val or amino acid analogue thereof and; LINKER represents a linking moiety for linking N terminus of AA1 to C terminus of AA4 to form a cyclic peptide containing a heterocyclic ring having 17 to 30 members. The cyclic peptides inhibit the interaction of vascular cell adhesion molecule-1 and fibronectin with integrin very late antigen 4 and have therapeutic applications such as in rheumatoid arthritis or multiple sclerosis.

Abstract: The disclosure relates to novel luliberin analogues which possess luliberin agonist activity, to processes for their manufacture and to compositions containing them. Typical of the peptides disclosed is ##STR1## in which A is D-Phe, D-Tyr(Me) or D-Ser(Bu.sup.t).