Intracerebral hemorrhage (ICH) is a major public health problem with highest mortality rate of all stroke subtypes and long-term disability. Since there are no available FDA-approved therapies for ICH it is of enormous importance to establish effective treatment for this medical condition. Following ICH the deposited blood is damaging initially via compression of the brain tissue (mass effect) and then via noxious chemical effect of hematoma components on brain tissue. The latter process involves toxicity of hemolytic products (e.g. iron), oxidative stress, pro-inflammatory responses, proteolytic enzymes-mediated extracellular matrix modification, blood brain barrier disruption and deadly cerebral edema. Lactoferrin (LTF) is a well-known endogenous glycoprotein with anti-microbial and immunoregulatory functions, in part through its effective sequestration of free iron. Using in vitr and in vivo models of ICH our novel findings demonstrate: (1) that LTF possess pleotropic mechanism of action that could effectively combat multifactorial aspects of ICH pathogenesis, (2) that it provides robust protective effect in experimental models of ICH, and that (3) a novel optimized LTF - fusion of human LTF (hLTF) with neonatal Fc receptor for IgG (PRC14) - is more effective than hLTF alone. The overall goal of this project is to begin the optimization process for using PRC14 as treatment for ICH. Our hypothesis is that the studies proposed here will initiate the preclinical development of PRC14 by starting the dose optimization process and the analysis of PRC14 t1/2.
Aim 1. To produce PRC14 and to determine the optimal dosing and therapeutic time window in ICH using adult male mice.
Aim 1 a. To optimize and produce PRC14 in Chinese Hamster Ovary cells (CHO). Focus will be to scale up production of PRC14. Criteria for acceptance: We will produce and purify (99% purity) sufficient quantity of PRC14 for this Phase I study (100mg).
Aim 1 b. Assess the efficacy of PRC14 in mice. We will test a dose range of PRC14 between 0.1mg-10mg/kg with therapeutic window of 3h, 12h, 24h and 48h. Criteria for acceptance: Improvement of neurological function by 20% with the therapeutic time window of 3h compared to the vehicle (p<0.05). All studies will follow NIH guidelines, RIGOR randomization approach and all analyses will be performed by the investigators blinded regarding the treatment assignments19-21.
Aim 2. To assess t1/2 and bioavailability of PRC14 in mice. The goal of this aim is to establish levels (bioavailable pool) of PRC14 in circulation an brain over 8 hours range, which is an equivalent of 10 x half-life time of natural LTF. We will measure PRC14 levels in serum and in the brain parenchyma by ELISA using goat anti-human LF antibodies. Criteria for acceptance: PRC14 will have at least 2-times extended half-life over the native LF and will reach brain tissue at least as efficiently as natural LTF.
Intracerebral hemorrhage (ICH) is the second most common and deadliest form of stroke. Currently, no pharmacologic treatment strategies exist for this devastating disease. The overall goal of this project is to develop a clinical prototype for early intervention in post-ICH complications using fusion of human lactoferrin (LF) with neonatal Fc receptor for IgG (PRC14). Studies proposed will initiate the preclinical development of this novel molecule and will involve developing optimal procedure for its production, determination of optimal dosing in animal model of ICH and initial pharmacokinetic studies. This will provide the foundation for future safety and efficacy studies in Phase II.