丹麦ALK-Abelló 制药公司于2009年2月24日对外宣布:其抗花粉过敏的疫苗Grazax片已获美国FDA的批准,用于5~17岁儿童和青少年患者花粉过敏的预防和治疗。 Grazax可以用来改善花粉患者的症状,同时也用于严重过敏性鼻炎和过敏性结膜炎患者的治疗,此外它也可用于对传统治疗药物如抗组胺药物与鼻用甾体类药物无效的患者。 Grazax含梯牧草Phleumpratense花粉中蛋白过敏原冻干提取物,其制备采用了CarSnal Health公司的速溶Zydis技术,为1日1次的速溶片,于花粉季节来临前至少8周开始服用即可,较传统的注射用过敏症疫苗更方便使用。据此ALK-Abelló公司希望通过将本品引入家庭药疗而拓展其免疫治疗市场。尽管所含过敏原只来自一种草本,本品仍有望适用于除儿童患者之外更广泛的枯草热患者,因为不同种类的草本植物中过敏原均相似。 GRAZAX® 是专为草花粉过敏的病人而制的舌下免疫治疗药片,每天服用一次便可。GRAZAX® 舌下药片能引发身体的防护免疫反应,阻止病人产生对草花粉的过敏反应。GRAZAX® 是一种快速溶化的舌下(在舌头之下)片剂,病人能自行服用,方便安全。 标准化特异性免疫治疗 要达至脱敏疫苗的标准化,生产过程必需具备以下条件:
Grazax, available in Europe but not in the U.S., is a fast-dissolving sublingual tablet taken once a day. A clinical trial to support U.S. approval of the immunotherapy is now underway. It may well revolutionize the way we treat allergies. The randomized, phase III study reported by Dr. Emminger began several months before the 2005 grass pollen season and included 634 patients in eight European countries. Active treatment ended in 2007 but the study remains blinded and participants will be followed through 2009. Adults 15 to 65 years old were included in the trial if they had a minimum two-year history of confirmed grass pollen allergy, no other perennial or seasonal allergies that overlapped with grass pollen season, and FEV1 lung function values of at least 70% predicted. "This was a real test for [the Grazax] tablet," Dr. Emminger said. In the 2007 season, median rhinovirus symptom scores were 3.2 for patients taking placebo compared with 2.0 for those taking Grazax. The percentage difference was nearly identical in the 2005 and 2006 seasons, although the absolute symptom scores declined in both groups as time went on. Dr. Emminger said this resulted from a combination of reduced average pollen counts and different patterns in rescue medication usage. By the third year, Grazax still appeared to cause more adverse effects than placebo, but the difference was less stark. Only 19% of patients receiving Grazax reported adverse effects in 2005, compared with 9% of the placebo group. The bottom line is that the side effect profile was minimal, it worked, and the positive effects seem to last for years. Dr. Emminger explained that the Grazax regimen is unlike most other allergic immunotherapies, which start with small doses and gradually build up. With Grazax, patients start with the full dose from day one, she said. The only problem I see with this is the one size fits all design. Our SLIT is not only based on what you are allergic to, but also how allergic you are. That allows us to start at the appropriate dose and then build to the maximum dose. This avoids unnecessary reactions and allows for more rapid dose escalation. |