The impact of Post-Transplant doxycycline in AL amyloidosis – updated results after Long-Term follow up

Abstract

Introduction

The current treatment paradigm of AL amyloidosis lacks effective fibril-directed therapies. Doxycycline has been shown to have anti-fibril properties in preclinical models. In 2012, we reported that posttransplant prophylaxis with doxycycline was associated with improved survival compared to penicillin in patients with haematologic response. We provide here updated results after long-term follow up.

Methods

We included 553 patients who underwent transplant between July 24^th, 1996, and June 24^th, 2014. Doxycycline 100 mg daily was used for prophylaxis in patients with penicillin allergy; since 2013, doxycycline was used as the standard for prophylaxis. Prophylaxis was typically continued for a year after transplant.

Results

The median follow-up from transplant was 12.7 years. Doxycycline was used for prophylaxis in 33% of patients; the rest received penicillin. The median time to next treatment was 6.0 (95%CI; 4.4–8.8) years and 6.0 (95%CI; 4.9–7.1) years in the doxycycline and penicillin groups, respectively (p = .89). The median overall survival was 12.0 (95%CI: 11.0–19.6) years and 11.0 (95%CI: 9.6–12.7) years in the 2 groups, respectively (p = .17). There was a minimal trend towards improved survival with doxycycline among patients with ≥ very good partial response and among patients with organ response that was not statistically significant.

Conclusion

After long-term follow-up, there is no clear evidence to support benefit of doxycycline in the post-transplant setting.

Keywords:

• Amyloidosis
• autologous stem cell transplant
• doxycycline
• penicillin
• prophylaxis
• survival

Disclosure statement

P.K. received research funding from Takeda Pharmaceuticals, Celgene, and Amgen. A.D. received research funding from Celgene, Millennium Pharmaceuticals, Pfizer, and Janssen and received a travel grant from Pfizer. D.D. serves as a consultant for Alexion, Apellis, GlaxoSmithKline, Janssen, Millenium/Takeda, and Rigel and received research funding from Juno Therapeutics and Karyopharm Therapeutics. M.A.G. served as a consultant for Millennium Pharmaceuticals and received honoraria from Celgene, Millennium Pharmaceuticals, Onyx Pharmaceuticals, Novartis, GlaxoSmithKline, Prothena, Ionis Pharmaceuticals, and Amgen. M.Q.L. received research funding from Celgene. N.L. serves on an advisory board for Takeda Pharmaceuticals. S.K.K. served as a consultant for Celgene, Millennium Pharmaceuticals, Onyx Pharmaceuticals, Janssen, and Bristol-Myers Squibb and received research funding from Celgene, Millennium Pharmaceuticals, Novartis, Onyx Pharmaceuticals, AbbVie, Janssen, and Bristol-Myers Squibb. The remaining authors declare no competing financial interests.

Data availability statement

The data that support the findings of this study are available from the corresponding author S.K.K upon reasonable request.