Kalydeco with an FEV1 of ~27% (homozygous delta-F508)

Treatment with Kalydeco on patients with the homozygous delta-F508 mutation will apparently pass FDA muster in July. My girlfriend is twenty-five and her doctor has indicated that her current baseline FEV1 is around twenty-seven percent, that this treatment is intended for those with an FEV1 of thirty-five percent or higher. Can someone elucidate what he's talking about here? I fully intend to fight tooth and nail for this treatment on its approval, but I'm scared there's something I don't know that will make this impossible.
Source: Cystic Fibrosis CFTR Modulation and Gene Therapy Forum - Category: Respiratory Medicine Authors: Tags: CFTR Modulation and Gene Therapy Talk Source Type: forums