Patient-Reported Outcome Tool for C. difficile-associated Diarrhea Accurately Addressed Patient Experience

Issue: Premier Issue 2014

WASHINGTON, D.C. — Patients reported that a new patient-reported outcome assessment tool developed based on the FDA PRO Guidance for Industry was easy to understand and relevant to their experience of Clostridium difficile-related diarrhea symptoms, according to data presented at ICAAC 2014.

“The reason why we have developed this new patient-reported outcome tool for C. difficile infection (CDI) is based on the recommendation by FDA,”Carl E. Nord, MD, Karolinska University Hospital, Stockholm, told Healio Gastroenterology. “They informed us there is no patient-reported outcome tool for [CDI]. Now we have developed a method based on interviewing patients.”

Carl E. Nord

With the goal of developing a disease-specific symptom patient-reported outcome (PRO) for C. difficile-associated diarrhea (CDAD),called CDAD-DaySyms, Nord and colleagues performed a cross-sectional, qualitative research study at five US study sites based on feedback from five clinical experts from the US and Europe. They conducted concept elicitation interviews of 18 CDAD patients and six nurses and two rounds of cognitive interviews of 10 and six patients to gain understanding of disease experience, test the validity of the PRO and revise it. Cognitive interviews were conducted by phone and collected information on the PRO’s relevance, acceptability and comprehensiveness, as well as interpretability and appropriateness of the instructions, response options and recall period.

Patients and nurses had similar reports, and concept saturation was reached for 18 CDAD symptoms including diarrhea, abdominal pain, fatigue and lightheadedness. Severity-based response options were selected for the PRO using a 5-point scale, and a 24-hour recall period was selected due to day-to-day symptom variability. Patients also reported that the PRO was relevant to symptoms and easy to understand. The PRO, which was revised after each round of interviews, also incorporates five symptom subdomains (diarrhea, abdominal discomfort, tiredness, light-headedness and other symptoms.

“We have come to the conclusion that [the tool] seems to work, and that the diarrhea symptoms, the abdominal discomfort, tiredness and light-headedness are the most important [symptoms to focus on], and the patients agreed upon that,” Nord said. “Now we are using this patient-reported outcome tool for evaluation in two phase 3 clinical trials worldwide where we are comparing cadazolid (Actelion Pharmaceuticals), which is a new agent for treatment of [CDI], vs. vancomycin. It will be very interesting to see if this system will work internationally.” – by Adam Leitenberger

For more information:

Nord CE. Abstract K-355. Presented at: Interscience Conference on Antimicrobial Agents and Chemotherapy; Sept. 5-9, 2014; Washington, D.C.

Disclosure: Nord is a scientific advisor on a review panel or advisory committee for Actelion Pharmaceuticals. Visit the ICAAC website for a list of the co-authors’ relevant financial disclosures.