There is a clear preference for animal surfacts over synthetic (exosurf). It has nothing to do with the source, but about perceived efficacy. If synthetic human surfactant is superior to any alternatives, I'm sure it will rapidly take market share. If it isn't equal to alternatives, then it faces an uphill battle that it will not win (neonatologists by and large keep up with the literature and they will not be swayed by marketing if there isn't the data to back it up). If it's just as good, then the battle can won with the right pricing and with agressive marketing (for example, "you don't want your patients to get MAD PIG disease, do you doctor?").
Off hand, I don't know if there is any significant chemical difference between the animal and human form of surfactant. Something to look up. My guess would be that the basic composition of the surfactant is very similar, and that of the protein is not as similar, but not as dissimilar as to generate an immune response (if I remember right, the animal proteins used in the adult trials of ards didn't generate a significant allergic response).
The purist would say that the properly conducted experiment would begin with the possibility that somehow animal surfactant is inherently superior to human surfactant. If you designed a trial, that could be your null hypothesis, and you would seek to disprove it. Consider, for example, the possibility that the surfactant needs of a premature infant are different than an adult. Perhaps they are more similar to that of an adult pig than that of an adult human. |
