New Library-Based Methods for Nontargeted Compound Identification by GC-EI-MS.

While gas chromatography mass spectrometry (GC-MS) has long been used to identify compounds in complex mixtures, this process is often subjective and time-consuming and leaves a large fraction of seemingly good-quality spectra unidentified. In this work, we describe a set of new mass spectral library-based methods to assist compound identification in complex mixtures. These methods employ mass spectral uniqueness and compound ubiquity of library entries alongside noise reduction and automated comparison of retention indices to library compounds.

Prevalence Estimation Methods for Time-Dependent Antibody Kinetics of Infected and Vaccinated Individuals: A Markov Chain Approach.

Immune events such as infection, vaccination, and a combination of the two result in distinct time-dependent antibody responses in affected individuals. These responses and event prevalence combine non-trivially to govern antibody levels sampled from a population. Time-dependence and disease prevalence pose considerable modeling challenges that need to be addressed to provide a rigorous mathematical underpinning of the underlying biology.

Improved Discrimination of Mass Spectral Isomers Using the High-Dimensional Consensus Mass Spectral Similarity Algorithm.

This study employs a high-dimensional consensus mass spectral (HDCMS) similarity scoring technique to discriminate isomers collected using an electron ionization mass spectrometer. The HDCMS method was previously introduced and applied to the discrimination of mass spectra of constitutional isomers, methamphetamine and phentermine, collected with direct analysis real-time mass spectrometry (DART-MS). The method formulates the problem of discriminating mass spectra in a mathematical Hilbert space and is hence called "high dimensional.

FDA Breakthrough Therapy Designation Reduced Late-Stage Drug Development Time.

The Food and Drug Administration's (FDA's) breakthrough therapy designation (BTD) program was created to increase patient access to safe and effective therapies by supporting the efficient clinical development of qualifying, clinically meaningful therapies. Using a new data set of key development milestones for drugs approved between 2006 and 2020, including both BTD drugs and a set of comparator drugs identified by FDA experts, we estimated the BTD program's impact on time spent in late-stage clinical development, measured as the elapsed time between a drug's end-of-Phase-II meeting with regulators and its approval for marketing. Our analysis suggests that the BTD program lowers late-stage clinical development time by 30 percent.