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  1. CDER Biomarker Qualification Program

Letter of Support (LOS) Initiative

Biomarker Letter of Support

What is a Letter of Support?

This is a letter issued to a requester that briefly describes CDER’s thoughts on the potential value of a biomarker and encourages further evaluation. This LOS does not imply qualification of a biomarker and does not endorse a specific biomarker test or device. It is meant to enhance the visibility of the biomarker, encourage data sharing, and stimulate additional studies.

Why Issue a Letter of Support?

An LOS is issued for promising biomarkers which have not yet been accepted into the CDER Biomarker Qualification Program. CDER encourages the early identification of novel biomarkers that may address drug development needs. The intent of the LOS is to enhance the visibility of these biomarkers, make public FDA’s support for continued development, and encourage data sharing and collaboration. When issued, both the LOS and the requester’s contact information are made publicly available on this website..

How to Request a Letter of Support?

An LOS request should be submitted along with a draft LOS in the format provided below.  This information should be submitted by email to CDER-BiomarkerQualificationProgram@fda.hhs.gov.

Information for Requester:

For more information, please contact CDER-BiomarkerQualificationProgram@fda.hhs.gov

FDA Issued Letters of Support

Requester
Biomarker(s)
Area(s) for Use in Drug Development
Issuance Date with Link to Letter of Support
Requester Contact

Critical Path Institute's (C-Path) Predictive Safety Testing Consortium (PSTC), Nephrotoxicity Working Group (NWG)

Urinary Biomarkers: Osteopontin and Neutrophil Gelatinase-associated Lipocalin (NGAL)

Early Clinical Drug Development

8/20/2014: Letter of Support (PDF)

Refer to Predictive Safety Testing Consortium Web Site

C-Path, PSTC, Skeletal Muscle Working Group (SMWG)

Serum and Plasma Biomarkers: Myosin Light Chain 3 (Myl3), Skeletal Muscle Troponin I (sTNI),  Fatty Acid Binding Protein 3 (FABP3), Creatine Kinase, Muscle Type (CK-M, the Homodimer CK-MM)

Early Clinical Drug Development

1/22/2015: Letter of Support (PDF)

Refer to Predictive Safety Testing Consortium Web Site

C-Path, Coalition Against Major Diseases Consortium (CAMD)

Cerebral Spinal Fluid (CSF) Analyte Biomarkers: Aβ1-42, Total tau, Phosphotau

Exploratory Prognostic Biomarkers for Enrichment in Early Stage Alzheimer’s Disease Clinical Trials

2/26/2015: Letter of Support (PDF)

Refer to Coalition Against Major Diseases Web Site

C-Path, CAMD

Magnetic Resonance Imaging Biomarker: Low Baseline Hippocampal Volume

Exploratory Prognostic Biomarkers for Enrichment in Early Stage Alzheimer's Disease Clinical Trials

3/10/2015: Letter of Support (PDF)

Refer to Coalition Against Major Diseases Web Site

C-Path, CAMD

Molecular Neuroimaging Biomarker: Dopamine Transporter (DAT)

Exploratory Prognostic Biomarkers for Enrichment in Early Stage Parkinson's Disease Clinical Trials

3/16/2015: Letter of Support (PDF)

Refer to Coalition Against Major Diseases Web Site

C-Path, Polycystic Kidney Disease (PKD) Outcomes Consortium

MRI, Computerized Tomography (CT), or Ultrasound (US) Biomarker: Total Kidney Volume (TKV)

Exploratory Prognostic Biomarker for Enrichment in Autosomal Dominant Polycystic Kidney

4/23/2015: Letter of Support (PDF)

Refer to Polycystic Kidney Disease Outcomes Consortium Web Site

Memorial Sloan-Kettering Cancer Center, Medivation Inc., and Janssen Diagnostics, LLC

Circulating Tumor Cell (CTC) Enumeration

Disease Activity Biomarker for use in Metastatic Castration-resistant Prostate Cancer (mCRPC)

9/25/2015: Letter of Support (PDF)

Debra J. Rasmussen 

Xhale, Inc.

2-Butanone in Human Breath

Monitoring Biomarker to Evaluate Drug-Dosing Compliance on a Dose-by-Dose Basis

11/19/2015:Letter of Support (PDF)

Donn Dennis

FLUIDDA

Functional Respiratory Imaging (FRI) of Lung and Airway Structural and Functional Parameters Measured by Low-dose High-definition Volumetric Computerized Tomography (HDCT) Scans and Quantitative Imaging Technology

Prognostic Biomarkers of Disease Progression and Pharmacodynamic Response for use in Idiopathic Pulmonary Fibrosis (IPF)  

6/6/2016: Letter of Support (PDF) 

Jan De Backer

Mosaiques-diagnostics
GmbH

CKD273
(Urinary Peptide Panel)

Prognostic Enrichment Biomarker Panel for use in Early Stage Diabetic Kidney Disease 

6/14/2016: Letter of Support (PDF) 

Harald Mischak

The Safer and Faster Evidence-based Translation Consortium (SAFE-T)

Cytokeratin 18 (CK‐18), Total and Hyperacetylated High Mobility Group Protein B1 (HMGB1), Osteopontin, and Macrophage Colony-Stimulating Factor 1 Receptor (CSF1R)

Exploratory Monitoring Biomarkers for Use in Drug Development as a Clinical Safety Assessment of the Risk of Drug-induced Liver Injury (DILI) Progression

7/25/2016: Letter of Support (PDF)

Drs. Gerd Kullak-Ublick, Sif Ormarsdottir, John-Michael Sauer or Douglas Keller or view either the Critical Path Institute Website or the IMI SAFE-T Consortium Website

Safer and Faster Evidence-based Translation (SAFE-T) Consortium and Predictive Safety Testing Consortium (PSTC) Soluble biomarkers of endothelial cell injury and inflammation: E-Selectin, P-Selectin, sICAM-1, sICAM-3, sVCAM-1, thrombomodulin VEGF, CRP, GROa, IL-6, IL-8, IP-10, I-TAC, MCP-1, MIG, SAA and MIP-1a Exploratory safety biomarkers for monitoring drug-induced vascular injury (DIVI) in early clinical drug development 11/7/2016: Letter of Support (PDF)

Michael Lawton, Tanja Zabka, Brad EnersonJohn-Michael Sauer  or view either the Critical Path Institute Website or the IMI SAFE-T Consortium Website

Safer and Faster Evidence-based Translation (SAFE-T) Consortium and Predictive Safety Testing Consortium (PSTC) urinary alpha-glutathione S-transferase (α-GST), urinary clusterin (CLU), urinary cystatin C (CysC), urinary Kidney Injury Molecule-1 (KIM-1), urinary neutrophil gelatinase-associated lipocalin (NGAL), urinary osteopontin (OPN), urinary albumin (ALB) and urinary total protein (TPRO) Exploratory safety biomarkers for monitoring drug-induced renal tubular injury in early clinical drug development 11/23/2016: Letter of Support (PDF) Gary Steven Friedman, Stefan Sultana, Jean-Charles Gautier, John-Michael Sauer or view either the Critical Path Institute Website or the IMI SAFE-T Consortium Website
TBI Endpoints Development (TED) Initiative and Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) Cortical contusions and diffuse axonal injury, as measured by magnetic resonance imaging (MRI) Exploratory prognostic enrichment biomarkers to identify patients who are likely to develop persistent disability during the course of mild traumatic brain injury (TBI) clinical trials 3/31/17: Letter of Support (PDF) Dr. Geoff Manley or view TED Initiative website and/or TRACK-TBI website
Health and Environmental Sciences Institute (HESI) Genomics Committee Genomic biomarker panel TGx-DDI Exploratory safety biomarker panel to facilitate safety genotoxicity assessment in nonclinical studies 10/24/17; Letter of Support (PDF) Syril Petit or view the HESI committee website
 TBI Endpoints Development (TED) Initiative and Transforming Research and Clinical Knowledge in TBI (TRACK-TBI)  Glial fibrillary acidic protein (GFAP) and ubiquitin carboxyl-terminal hydrolase-L1 (UCH-L1) in blood  Exploratory prognostic enrichment biomarkers to identify patients who are likely to develop persistent disability during the course of mild traumatic brain injury (TBI) clinical trials   1/10/18:Letter of Support (PDF) Dr. Geoff Manley or view TED Initiative website and/or TRACK-TBI website
 FLUIDDA, Inc.  Functional Respiratory Imaging (FRI) of Lung and Airway Structural and Functional Parameters Measured by Low-dose High-definition Volumetric Computerized Tomography (HDCT) Scans and Quantitative Imaging Technology  Exploratory pharmacodynamic/response (PD/R) biomarkers for use in bioequivalence (BE) studies of locally-acting orally-inhaled drug products (LAOIDP) in clinical trials of patients with conditions of the lung 1/10/18: Letter of Support (PDF) Jan De Backer
 NeuroRx, Inc.  Glx (Glutamine and Glutamate) in the brain as measured by Magnetic resonance spectroscopy  As a pharmacodynamic biomarker, an objective imaging biomarker measure of depression to be used in conjunction with current measures of depression (rating scales) in clinical trials. 4/3/18: Letter of Support (PDF) Johnathan C. Javitt
sRNAlytics, Inc. Isomicro-RNAs’ levels in blood as measured by assay As a monitoring biomarker, indicating progression of Huntington’s Disease in patients bearing the HD mutation 1/17/19: Letter of Support (PDF) David W. Saltzman

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