LSBC biomanufacturing approach relies on the use of tobacco plants as biological factories. The company inserts the genetic sequence coding for the desired compound - in this case a secretory immunoglubulin A (SIgA) - into a virus that infects tobacco plants. This tobacco mosaic virus is based on RNA, so it does not combine with the tobacco plant's genetic material. This does away with the need to genetically modify the plant, avoiding the high cost and length of time taken to develop transgenics and also bypassing environmental concerns about GM material.
Using LSBC's process, regular tobacco is planted and sprayed with the virus once the plants have emerged. The tobacco is then harvested as normal, and further processing takes place to extract and purify the target protein.
Making pharmaceuticals in crop plants such as tobacco is an attractive proposition because they are inexpensive to grow, and could produce vast quantities of drugs or vaccines at low cost, potentially making it possible to make drugs that were not economically feasible before. But moves in this area have been met with dismay by environmentalist groups, alarmed that the GM traits could find their way into the food chain.
CaroRx is claimed to be the world's first recombinant plant-made antibody - or 'plantibody' - and has been shown in clinical studies to prevent the adhesion to the tooth surface of decay causing bacteria.
Planet's tobacco plants expressing the proprietary CaroRx Protected SIgA will be extracted by LSBC at its Owensboro, Kentucky, manufacturing facility. CaroRx is currently approved for sale as a medical device in the European Union.
"This new phase of bioprocessing work that we have commissioned at LSBC continues last year's successful production of developmental clinical and analytical lots of CaroRx," said Planet's CEO, Elliott Fineman. The new batches will be used in marketing efforts in Europe and to supply a clinical trials programme in the US, he added.