Patient Centric Microsampling to Support Paxlovid Clinical Development: Bridging and Implementation

Nirmatrelvir is a potent and selective severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) main protease inhibitor. Nirmatrelvir co-packaged with ritonavir (as PAXLOVID) received US Food and Drug Administration (FDA) Emergency Use Authorization (EUA) on December 22, 2021, as an oral treatment for coronavirus disease 2019 (COVID-19) and subsequent new drug application approval on May 25, 2023. Pharmacokinetic (PK) capillary blood sampling at-home using Tasso-M20 micro-volumetric sampling device was implemented in the program, including three phase II/III outpatient and several clinical pharmacology studies supporting the EUA. The at-home sampling complemented venous blood sampling procedures to enrich the PK dataset, to decrease the need for patients' site visit for PK sampling, and to allow different sampling approaches for flexibility and convenience. To demonstrate concordance/equivalence, bridging between venous plasma and Tasso dried blood results was conducted by comparing concentrations and derived PK parameters from both sampling approaches. In addition, a two-compartment population PK model was utilized to bridge the plasma and Tasso data by estimating the PK parameters using blood-to-plasma ratio as a slope parameter. Operational challenges were successfully managed to implement at-home PK sampling in global phase II/III trials. Sample quality was generally very good with less than 3% samples deemed as "not usable" from over 800 samples collected in all the studies. Experience gained from sites and patients will guide future broader implementations.

Using Mitra sampling to support first-in-human pharmacokinetic evaluations for PF-07059013

Aim: A sensitive and selective method for the determination of PF-07059013 in dried blood collected by Mitra™ tips was developed and qualified from 50 to 50,000 ng/ml. Materials & methods: PF-07059013 is isolated from 10 μl of human dried blood by extraction with methanol and analyzed by HPLC-MS/MS. Results & conclusions: In addition to routine validation elements, impact of hematocrit and Mitra tip's lot-to-lot variation on assay accuracy were evaluated. The qualified method was used in one clinical study with excellent performance. Correlation coefficient between blood concentrations obtained from liquid-incurred blood samples and dried-incurred blood samples is 0.95. Clinical Trial Registration: NCT04323124 (ClinicalTrials.gov).

2022 White Paper on Recent Issues in Bioanalysis: ICH M10 BMV Guideline & Global Harmonization; Hybrid Assays; Oligonucleotides & ADC; Non-Liquid & Rare Matrices; Regulatory Inputs (Part 1A - Recommendations on Mass Spectrometry, Chromatography and Sample Preparation, Novel Technologies, Novel Modalities, and Novel Challenges, ICH M10 BMV Guideline & Global Harmonization Part 1B - Regulatory Agencies' Inputs on Regulated Bioanalysis/BMV, Biomarkers/CDx/BAV, Immunogenicity, Gene & Cell Therapy and Vaccine)

The 16th Workshop on Recent Issues in Bioanalysis (16th WRIB) took place in Atlanta, GA, USA on September 26-30, 2022. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 16th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on the ICH M10 BMV final guideline (focused on this guideline training, interpretation, adoption and transition); mass spectrometry innovation (focused on novel technologies, novel modalities, and novel challenges); and flow cytometry bioanalysis (rising of the 3rd most common/important technology in bioanalytical labs) were the special features of the 16th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2022 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2022 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 1A) covers the recommendations on Mass Spectrometry and ICH M10. Part 1B covers the Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine. Part 2 (LBA, Biomarkers/CDx and Cytometry) and Part 3 (Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity) are published in volume 15 of Bioanalysis, issues 15 and 14 (2023), respectively.

Leveraging patient-centric sampling for clinical drug development and decentralized clinical trials: Promise to reality

Advances in the technologies to enable patient-centric sampling (PCS) have the potential to improve blood sample collection by enabling clinical trial participants to collect samples via self-collection or with the help of a caregiver in their home. Typically, blood samples to assess pharmacokinetics and pharmacodynamics of a drug during clinical development are collected at a clinical site via venous blood draw. In this position paper by the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ), the potential value PCS can bring to patients, to the clinical datasets generated, and to clinical trial sponsors is discussed, along with considerations for program decision making, bioanalytical feasibility, operations, and regulatory implications. With an understanding of the value of PCS and considerations when implementing during clinical drug development, we can bring the promise of PCS closer to reality and enable decentralized clinical trials.

Pharmacokinetics of Oral Nirmatrelvir/Ritonavir, a Protease Inhibitor for Treatment of COVID-19, in Subjects With Renal Impairment

Nirmatrelvir coadministered with ritonavir is highly efficacious in reducing the risk of coronavirus disease 2019 (COVID‐19) adverse outcomes among patients at increased risk of progression to severe disease, including patients with chronic kidney disease. Because nirmatrelvir is eliminated by the kidneys when given with ritonavir, this phase I study evaluated the effects of renal impairment on pharmacokinetics, safety, and tolerability of nirmatrelvir/ritonavir. Participants with normal renal function (n = 10) or mild, moderate, or severe renal impairment (n = 8 each) were administered a single 100‐mg nirmatrelvir dose with 100 mg ritonavir given 12 hours before, together with and 12 and 24 hours after the nirmatrelvir dose. Systemic nirmatrelvir exposure increased with increasing renal impairment, with mild, moderate, and severe renal impairment groups having respective adjusted geometric mean ratio areas under the plasma concentration‐time profile from time 0 extrapolated to infinite time of 124%, 187%, and 304% vs. the normal renal function group. Corresponding ratios for maximum plasma concentration were 130%, 138%, and 148%. Apparent clearance was positively correlated with estimated glomerular filtration rate, and geometric mean renal clearance values were particularly lower for the moderate (47% decrease) and severe (80% decrease) renal impairment groups vs. the normal renal function group. Nirmatrelvir/ritonavir exhibited an acceptable safety profile; treatment‐related adverse events were mild in severity, and there were no significant findings regarding laboratory measurements, vital signs, or electrocardiogram assessments. These findings led to a dose reduction recommendation for nirmatrelvir/ritonavir in patients with moderate renal impairment (150/100 mg nirmatrelvir/ritonavir instead of 300/100 mg twice daily for 5 days). NCT04909853.