Effect of pirfenidone injection on ferret vocal fold scars: A preliminary in vivo study

One Year Outcomes and Longitudinal Changes in Voice Improvement With Single High Dose Intracordal Trafermin Injections for Age-Related Vocal Fold Atrophy

OBJECTIVE

Although intracordal trafermin injection has been performed in the treatment of age-related vocal fold atrophy, the effects of single high dose trafermin injections are unknown. In this study, we examined the 1 year outcomes and longitudinal changes in voice improvement with single high dose intracordal trafermin injections.

STUDY DESIGN

Retrospective study with approval by our Ethics Committee.

METHODS

The medical records of 34 patients who underwent single high dose (50ug per side) intracordal trafermin injections under local anesthesia for vocal fold atrophy were retrospectively reviewed at 1 month pre-injection and 1 month, 6 months and 1 year post injection.

RESULTS

Maximum phonation time (MPT), pitch range (PR), Japanese version of voice handicap index (VHI), grade of GRBAS evaluation, and jitter% improved significantly at 1-year post-injection compared to 1-month pre-injection. MPT and PR improved as early as 1-month post-injection and continued to improve most at 1-year post-injection. VHI showed negative progression from 6-months to 1-year post-injection, during which time the speaking fundamental frequency (SFF) changed to the high pitch in men.

CONCLUSIONS

Single high dose intracordal trafermin injections can be expected to improve voice in the early post-injection period and to maintain its effect for 1 year. SFF may play a role in worsening VHI in men.

LEVEL OF EVIDENCE

level 4.

Current approaches to management of vocal fold scar

PURPOSE OF REVIEW

Vocal fold (VF) fibrosis remains an insoluble problem in most cases, with a severe impact on vocal quality and effort. This review examines current investigations and research strands that explore the understanding of VF wound healing and applied treatments for the management of VF scar.

RECENT FINDINGS

Recent work focused on VF fibrosis has examined wound healing in the glottis, fibrosis-modifying medication, and tissue engineering approaches that span cytokine and growth factor therapy, scaffold and cell delivery platforms, seeded scaffolds, conditioned media and stem cell therapy. Many show promise and may deliver improvements in the wound bed favouring less fibrogenic healing patterns, ultimately with the goal of preserving or restoring VF vibration. Further collaborative research is required that examines combined approaches, long term outcomes, better three-dimensional modelling of cell-cell interactions and delivery modalities for molecular therapies.

SUMMARY

VF fibrosis research continues to expand and explore a variety of mechanistic pathways in order to understand VF healing and identify novel and complementary targets for manipulation. Many different approaches show promise and may also offer synergistic benefits. Research continues to strive for healing that more closely resembles true VF architecture and function.

Novel approach for attenuation of pirfenidone-induced digestive symptoms: a respirable powder formulation of pirfenidone

Aim: Orally taken pirfenidone (PFD) often causes digestive symptoms. A respirable powder formulation of PFD (PFD-RP) was previously developed, and this study aimed to verify the risk of digestive symptoms after insufflation of PFD-RP. Materials & methods: Intestinal motility and gastrointestinal exposure levels was evaluated in PFD-RP (0.3-mg PFD/rat: a pharmacologically effective dose) and orally taken PFD (10-100 mg/kg) groups. Results & conclusion: Orally taken PFD at doses above 30 mg/kg significantly inhibited intestinal motility. In contrast, insufflated PFD-RP led to comparable intestinal motility in control group, and gastrointestinal exposure levels in PFD-RP group were markedly lower than those in orally taken PFD groups. Inhalation therapy using PFD-RP may be efficacious to reduce the risk of digestive symptoms frequently induced by orally taken PFD.