Are there any ongoing or planned studies on vaccines and diverticulitis?

The short version: the retrieval still contains no study on diverticulitis and vaccination. The follow-up does not change that.

The previous answer was correct on the core point: the question is unstudied in the records you were given. None of the 27 records name diverticulitis, diverticular disease, or colonic complications as an outcome. The closest is a study on gastrointestinal symptom improvement in long COVID after vaccination [4], which does not address diverticulitis. The rest cover skin reactions, kidney disease, myocarditis, pituitary disorders, and animal vaccines — none relevant.

The follow-up asks whether there are ongoing or planned studies. The retrieval contains no registry entries, no trial protocols, no funding announcements, and no preprints describing a planned diverticulitis-vaccine study. A search of clinical trial registries was not part of this retrieval, so I cannot say whether one exists outside it. But the records you have do not mention one.

My call: no evidence of a planned or ongoing study was found in this retrieval. That does not mean none exists — only that it was not surfaced here. Confidence: low, because the retrieval was not designed to find trial registrations.