merozoite surface protein 3 long synthetic peptide

MSP3 Long Synthetic Peptide (MSP3-LSP) is a malaria vaccine candidate derived from the conserved C-terminal region of Plasmodium falciparum merozoite surface protein 3. The vaccine consists of a 95-amino acid synthetic peptide that has undergone clinical testing for safety and immunogenicity. ## Description MSP3-LSP is a long synthetic peptide vaccine candidate targeting malaria. It corresponds to a fully conserved region covering amino acids 181-276 of the C-terminal region of MSP3 from Plasmodium falciparum strain Fc27[1][3]. The peptide sequence is: RKTKEYAEKAKNAYEKAKNAYQKANQAVLKAKEASSYDYILGWEFGGGVPEHKKEENMLSHLYVSSKDKENISKENDDVLDEKEEEAEETEEEELE[3]. This vaccine candidate works by inducing specific antibodies, particularly cytophilic IgG1 and IgG3 antibodies, which can inhibit P. falciparum erythrocytic growth through a monocyte-dependent mechanism[2]. MSP3-LSP has been shown to induce strong T-helper 1 and B-cell responses in clinical trials[2]. ## Development and Clinical Trials MSP3-LSP has undergone several clinical trials: - A Phase Ia trial in European malaria-naïve volunteers demonstrated safety and immunogenicity, inducing strong T-helper 1 and B-cell responses[2]. - A Phase Ib trial in semi-immune adult volunteers in Burkina Faso found the vaccine to be safe at a dose of 30 μg, with less local reactogenicity in P. falciparum exposed individuals than observed in naïve volunteers[2]. - A subsequent Phase Ib dose-escalation trial in children aged 12-24 months in Burkina Faso assessed the safety and immunogenicity of 15 μg and 30 μg doses[6]. The vaccine has been tested with different adjuvants, including aluminum hydroxide and Montanide ISA 720[1][5]. ## Manufacturing MSP3-LSP is produced by solid-phase synthesis, a single-step process that allows for the creation of the long polypeptide chain[2][5]. The vaccine undergoes quality control processes, including assessment of potency, antigen content, and conformity to specifications by HPLC and mass-spectrometry[3]. For clinical trials, the vaccine was produced by SYNPROSIS in France[2][3]. It was available in a multi-dose vial in lyophilized form and reconstituted prior to administration with an adjuvant[3]. ## Safety and Immunogenicity Clinical trials have shown that MSP3-LSP is generally safe, though it appears to be more reactogenic at the injection site than comparator vaccines, with some volunteers experiencing grade 3 local reactions (swelling and induration)[2][6]. Most adverse events reported were mild to moderate in severity, and all resolved without sequelae[6]. The vaccine has demonstrated good immunogenicity, eliciting high levels of anti-MSP3 specific IgG1 and IgG3 antibodies in volunteers, with very little or no increase in IgG2, IgG4, and IgM classes[6]. This antibody profile is significant as it predominantly induces the isotypes involved in the monocyte-dependent mechanism of P. falciparum parasite-killing[6].

Other names

MSP3 Long Synthetic PeptideMSP-3 Long Synthetic PeptideMSP 3 Long Synthetic Peptide