Company: OCEA
Filing Date: 2025-04-08
Form Type: 10-K
Source: 0001641172-25-003155
Chunk: 2088

Company: Ocean Biomedical, Inc.
Filing Date: 2025-04-08
Form: 10-K
Item: Item 1A
Chunk 2088
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ia seven days after challenge. In all five experiments performed,
by day seven to eight after challenge, control mice had high parasitemia with associated morbidity, whereas none of the vaccinated mice
had high parasitemia or overt morbidity. In experiments with long-term follow-up, both active immunization with rPbSEA-1 and passive
transfer of antibodies to PbSEA-1 significantly reduced parasitemia and delayed mortality.

In
human observational studies conducted in Tanzania, individuals with naturally acquired antibodies to PfSEA-1 were associated with significant
protection from severe malaria, with no cases occurring while children had detectable antibodies to PfSEA-1 (Fig 9). In a second longitudinal
Kenyan cohort, anti–PfSEA-1 antibodies were associated with significant protection against parasitemia in adolescents and young
adults. Individuals with detectable IgG anti–rPfSEA-1 antibodies had 50% lower parasite densities over 18 weeks of follow-up compared
with individuals with no detectable IgG anti-rPfSEA-1A antibodies.

29

Figure
9. Antibodies to rPfSEA-1A predict reduced malaria severity and parasitemia. Incidence of severe malaria and death in Tanzanian children
aged one and a half to three and a half years during intervals with detectable and undetectable antibodies to PfSEA-1 (1688 and 23,806
weeks, respectively). No cases of severe malaria or death occurred during intervals with detectable antibodies to rPfSEA-1A. Error bars
represent 95% CI.

Based
on these data, we hypothesize that vaccination of humans with PfSEA-1 could generate antibodies that trap parasites within a red cell
and lead to parasite death.

PfGARP
is a parasite antigen with a mass of 80 kilodaltons that is expressed on the external surface of erythrocytes (red blood cells) infected
by early-to-late-trophozoite-stage parasites.

Antibodies
against PfGARP kill trophozoite-infected erythrocytes in culture by inducing programmed cell death in the parasites (see Fig 10). Vaccinating
non-human primates with PfGARP has been shown to protect against a challenge with P. falciparum (see Fig 11). Furthermore, longitudinal
cohort studies have shown that, compared to individuals who had naturally occurring anti-PfGARP antibodies, Tanzanian children without
anti