In June 2026, KAKEN PHARMACEUTICAL CO.,LTD. issued a notice on the proper use of Fiblast Spray. Cases of induration and bulging have been reported following combined PRP and bFGF injections for facial wrinkles and depressions, reinforcing the view that injection is outside the approved use of this product, which is intended for external use.
A survey by the Japanese Society of Aesthetic Surgery reported that approximately 40% of cases of site induration or bulging associated with injection therapies using specified cell-processed products or growth factors resulted from combined injections of PRP and bFGF. In connection with this, it was explained that induration is caused by fibrosis, while bulging of the subcutaneous fat layer is thought to result from fat induction.
In June 2026, KAKEN PHARMACEUTICAL CO.,LTD. strongly urged proper use of Fiblast® Spray 250 and 500, which it manufactures and markets, stating that they are products for external use and that the efficacy and safety of administration by injection have not been established. Subsequent reports have stressed the importance of avoiding problems in facial injection therapies.
Some cosmetic surgery clinics perform what is described as “injections of Fiblast Spray,” but cases have reportedly occurred in which the treated areas became uneven despite favorable outcomes in other cases. The misuse of injection concentrations was identified as a major risk factor. The manufacturer has repeatedly published statements prohibiting injection, and the product must be used at the proper concentration and for its intended purpose.
Kenichi Homma (本間 賢一) of Sapporo Cosmetic and Plastic Surgery stated that he does not perform injections because they carry risks, again underscoring the importance of appropriate knowledge and judgment. In his own comments, he also called for proper handling even of refrigerated products and urged the avoidance of problems caused by misuse.