PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Letter”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2026

Understanding FDA's reasons for nonapproval: A systematic review of complete response letters in cell and gene therapy.

BACKGROUND AIMS: Cell and gene therapy products face unique regulatory challenges due to their biological complexity and the stringent expectations for manufacturing control, analytical testing, and clinical assessment. As the pipeline grows, understanding the drivers of FDA non‑approval is increasingly important for improving first‑cycle success and reducing development delays. In this study, we aimed to characterize the frequency and impact of refuse‑to‑file actions, major amendments, and complete response letters issued for biologics licensing applications; and to identify recurring patterns of deficiencies contributing to delayed approval. METHODS: Publicly available documents were extracted from the FDA website. Data from each approved cell and gene therapy product's regulatory history-including complete responses, major amendments, inspection timing, and cited deficiencies-were compiled and categorized across clinical, quality, and labeling domains. RESULTS: Analysis showed that informational deficiencies were common across modalities. Major amendments occurred in roughly half of applications, and complete responses had the most significant impact. Quality deficiencies appeared in all complete responses and were the predominant barrier, while clinical and labeling issues were less frequent but meaningful when present. CONCLUSION: Overall, these findings highlight the need for proactive FDA engagement, comprehensive readiness, and early inspection preparation to reduce regulatory risk and improve first cycle approval outcomes.

Humans↗
PubMed1978

[Study on the effectiveness of the "Berlin Letters for Seniors (author's transl)].

The effectiveness of the "Berlin Letters for Seniors" (LFS) will be tested by a longitudinal study. Two Measurement Points (MP) are scheduled: 1976 and 1978. The total sample (N = 3000) comprehends two subsamples of receivers and non-receivers. Data were/will be collected by a questionnaire. A preliminary analysis of the MP I data shows that the two subsamples are comparable as to demographic variables and relevant attitudes; so they may serve as experimental versus control group. An examination of what the readers' concept of the LFS was like, proved that though reservation was recognizable approval prevails.

Aged↗