MiZ Company Limited of Japan makes hydrogen (H2) gas therapy machine and is publishing positive case reports to promote their product. Treatment was not successful for their best patient because the patient still has ME/CFS. The title of this academic paper is misleading.
Patient 1 was vaccinated twice 
, with symptoms worsening after each vaccination.
The patient started with really severe ME/CFS, got better, and hit a plateau. They still have ME/CFS.
Presumably this is their best patient because the other 3 patients in the case series don’t have data published for them (???).