The 18th Workshop on Recent Issues in Bioanalysis (18th WRIB) took place in San Antonio, TX, USA on May 6-10, 2024. Over 1100 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 18th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week to allow an exhaustive and thorough coverage of all major issues in bioanalysis of biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on "IVDR Implementation in EU & Changes for LDT in the US" and on "Harmonization of Vaccine Clinical Assays Validation" were the special features of the 18th 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 2024 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 2024 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 2) covers in the Part 2A the recommendations on Biomarkers/BAV, IVD/CDx, LBA and Cell-Based Assays and in Part 2B the Regulatory Inputs on these topics. Part 1 (Mass Spectrometry Assays and Regulated Bioanalysis/BMV) and Part 3 (Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity) are published in volume 17 of Bioanalysis, issues 5 and 3 (2025), respectively.