How long ago was her treatment with ATG and what are her blood counts? It can take up to a year before you see a response.
There's not really an age limit for High Dose Cytoxan. I would highly recommend that if you are considering High Dose Cytoxan, to contact Dr. Robert Brodsky at Johns Hopkins. High Dose Cytoxan is not ususally done outside of Baltimore without some guidance from Hopkins. I really encourge you to speak with Dr. Brodsky directly.
Hy Cy is not as effective if a patient has gone through ATG and failed. It's best as the first line of treatment.
You should also be considering a second round of ATG and/or bone marrow transplants.
At 31, your girlfriend is not too old for any of the SAA treatments.
At a minimum, go to one of the Center's of Excellence Ruth posted for second opinion.
Marlene, wife to John DX w/SAA April 2002, Stable partial remission; Treated with High Dose Cytoxan, Johns Hopkins, June 2002. Final phlebotomy 11/2016. As of January 2017, FE is 233, HGB 11.7, WBC 5.1/ANC 4.0, Plts 90K.