Cystic Fibrosis News Digest — Issue 02

A P Sawant, N Shaw, I J Clifton, H Saumtally, D G Peckham

Summary: A UK regional adult CF centre reports four cases (4.6%) of new or worsening neuropsychiatric symptoms among 84 patients started on standard-dose vanzacaftor-tezacaftor-deutivacaftor (VTD), the newest triple-combination CFTR modulator. Three of the four cases involved suicidal ideation and ultimately required switching back to elexacaftor-tezacaftor-ivacaftor (ETI), with rapid symptom resolution. Separately, three patients with pre-existing mental health conditions were proactively started on a reduced dose, with two of three achieving meaningful sweat chloride reduction and no adverse psychiatric events.

Why it matters: Neuropsychiatric adverse effects with ETI prompted post-marketing warnings, and this report confirms that VTD carries a similar — and possibly more severe in character — signal, now formally acknowledged by regulators. As VTD enters broader clinical use, particularly among patients switching from ETI, clinicians need a concrete framework for pre-treatment psychiatric assessment, monitoring protocols, and dose-adjustment strategies. The proactive reduced-dose approach in high-risk patients is a pragmatic contribution that deserves prospective evaluation. The fact that all four cases were reported to the UK MHRA Yellow Card scheme is appropriate and supports ongoing pharmacovigilance.

Expert perspective: This is a case series of four events at a single centre — inherently limited in sample size, generalizability, and the ability to distinguish drug-attributable causation from coincidence or natural fluctuation in mental health. The authors are appropriately candid about the most important methodological weakness: case ascertainment was purely clinical rather than through systematic structured psychiatric screening. This virtually guarantees underdetection; the true rate at this centre could be higher, and at centres without a proactive safety culture, it could be substantially underreported. The 4.6% crude rate is superficially comparable to published ETI real-world rates (~7–7.9%), but direct comparison is premature given different denominators, different follow-up durations, different baseline psychiatric burden across cohorts, and — critically — different severity profiles. The authors' observation that suicidal ideation appeared more frequent with VTD than in prior ETI series is clinically important but statistically uninterpretable from four cases.

The reduced-dose strategy in the three high-risk patients is biologically plausible and pharmacologically interesting, particularly given that deutivacaftor's modified pharmacokinetics theoretically affect CNS exposure. However, two of three achieving sweat chloride below 40 mmol/L is encouraging but cannot be taken as proof of therapeutic equivalence or safety — a controlled assessment with systematic outcomes measurement would be needed. Importantly, the mechanism linking CFTR modulation to neuropsychiatric effects remains poorly understood, and it is not yet clear whether the effect is class-specific, molecule-specific, or depends on individual CNS CFTR expression or vulnerability.

From a pharmacovigilance standpoint, this report performs a genuine service: it documents real-world signal with sufficient clinical detail to be actionable, it models transparent adverse-event reporting to a national regulator, and it raises the specific question of whether patients with pre-existing psychiatric conditions require a dose-modified initiation protocol. What is now needed is a prospective, multi-centre surveillance study with validated psychiatric instruments administered at standardized intervals after VTD initiation — ideally embedded within existing national CF registries — so that incidence, severity, risk factors, and dose-response relationships can be characterized with the rigor the question deserves.

Relevance: Cystic Fibrosis

Source: https://pubmed.ncbi.nlm.nih.gov/42763277/

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Yunxia O'Malley, Henry Keen, Ian M Thornell et al.

Summary: This laboratory study examined whether restoring CFTR function — via adenoviral transfection or elexacaftor/tezacaftor/ivacaftor (ETI) — affects growth, migration, and gene expression in pancreatic ductal adenocarcinoma (PDAC) cell lines and primary pig pancreatic duct epithelial cells. The investigators found that CFTR-deficient cells showed increased proliferation and migration, and that ETI treatment shifted cell cycle kinetics toward slower replication and suppressed pro-growth transcriptional pathways, including Wnt signaling and key cell cycle regulators, without inducing apoptosis. Public datasets confirmed reduced CFTR expression in human pancreatic cancer tissue relative to normal pancreas.

Why it matters: People with cystic fibrosis carry a substantially elevated risk of gastrointestinal cancers, including pancreatic cancer, compared with the general population — a concern that grows more pressing as CFTR modulators extend life expectancy and as more patients reach ages at which cancer risk accumulates. If CFTR restoration has genuine anti-proliferative effects in pancreatic ductal epithelium, this would carry both mechanistic and clinical implications: it could partially explain cancer risk differences across CFTR genotypes, and it raises the hypothesis that ETI use might eventually prove protective against PDAC in people with CF. That hypothesis deserves rigorous evaluation, though it cannot be confirmed by the present data.

Expert perspective: This is scientifically interesting preclinical work, but it sits firmly in the "promising but preliminary" category and should be read with disciplined expectations. The experimental systems are highly artificial: PANC-1 and CFPAC-1 are established cancer cell lines with extensively remodeled genomes and signaling contexts that diverge substantially from normal or even premalignant pancreatic duct epithelium in a living CF patient. Cell lines are useful for mechanistic hypothesis generation but are notoriously poor predictors of in vivo biology, let alone clinical outcomes.

Restoring CFTR via adenoviral transfection in cancer cell lines produces an acute, supraphysiological expression environment categorically different from the chronic, partial correction achieved by ETI in F508del patients in vivo. The transcriptomic findings — downregulation of cyclins, CDKs, MCM complexes, and Wnt pathway activators in ETI-treated cells — are associative; whether these changes reflect a primary CFTR-mediated effect or secondary responses to altered ion transport, pH, or metabolic state is not established. Notably, ETI appears to slow rather than kill cells — a cytostatic rather than cytotoxic phenotype — and whether this translates into meaningful cancer risk reduction over a lifetime of exposure cannot be addressed by short-term assays. The pig primary duct epithelial cell experiments with wild-type, F508del, and null CFTR genotypes add biological credibility and represent a more physiologically relevant model, which is a methodological strength.

The clinical question that ultimately matters — whether ETI use in people with CF reduces pancreatic cancer incidence or delays its onset — will require long-term registry-based or epidemiological study. CF patient registries, including the US CF Foundation Patient Registry and the European CF Society Patient Registry, are potentially well positioned to begin tracking cancer outcomes longitudinally with adequate granularity, provided ascertainment and linkage to cancer registries are prioritized. The authors are careful not to overclaim, and the work appropriately frames its implications as a starting point for further investigation in organoid models, animal models, and ultimately clinical cohorts — not as a basis for any change in current clinical practice or cancer surveillance recommendations.

Relevance: Cystic Fibrosis

Source: https://pubmed.ncbi.nlm.nih.gov/42731950/

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Antoine Bronstein, Elise Zitta, Oussama Saidi et al.

Summary: This controlled cross-sectional study compared peripheral muscle function in 56 adults with cystic fibrosis (95% on elexacaftor/tezacaftor/ivacaftor for a mean of approximately 31 months) against 46 healthy age- and sex-matched controls. People with CF showed statistically and clinically meaningful deficits in quadriceps strength, quadriceps endurance, quadriceps muscle thickness, and handgrip strength. Critically, quadriceps strength remained lower even after normalization to muscle thickness, suggesting impairment beyond simple muscle atrophy or physical inactivity.

Why it matters: The widespread adoption of highly effective CFTR modulator therapy (HEMT) has transformed the disease trajectory for many people with CF, raising a reasonable but important question: have extrapulmonary manifestations such as muscle dysfunction resolved, attenuated, or persisted? This study provides the first relatively large, systematically conducted controlled assessment addressing that question. The finding that intrinsic muscle quality — not merely muscle bulk or sedentary behavior — appears compromised has direct implications for rehabilitation, exercise programming, and long-term disease management, even in an era when lung function is substantially preserved by modulator therapy.

Expert perspective: The study is methodologically careful in several respects. The sample size of 56 CF participants is modest but is described as the largest controlled study of this specific question to date. Measurement of muscle function followed international recommendations, multiple muscle groups were evaluated, and accelerometry was used to objectively quantify physical activity — a meaningful improvement over self-report. Effect sizes (rank-biserial correlations of 0.27–0.47 and Cohen's d of 0.48) are in the small-to-moderate range, indicating real but not dramatic impairments; the clinical framing as "clinically relevant" is reasonable rather than hyperbolic.

However, several limitations deserve attention. The cross-sectional design precludes any causal inference about HEMT's effect on muscle function over time. There is no pre-HEMT baseline for these participants, so it is impossible to determine whether the deficits observed represent residual dysfunction that has improved from a worse pre-modulator state, or dysfunction that has been entirely unresponsive to HEMT. The mean FEV₁ of 77% predicted indicates a relatively well-preserved lung function cohort, which may limit generalizability to more severely affected individuals. The authors' inference that "intrinsic muscle alterations" are present — based on strength remaining lower after normalization to thickness — is plausible and mechanistically interesting, given that CFTR is expressed in skeletal muscle and mitochondrial dysfunction in CF muscle has been reported, but normalization to ultrasound-measured thickness is an imperfect proxy for true muscle quality, and residual confounding from nutritional adequacy, chronic systemic inflammation, and prior corticosteroid use cannot be excluded.

The practical message is sound and not overstated: clinicians should not assume that HEMT has resolved muscle dysfunction, and exercise and rehabilitation interventions remain relevant components of comprehensive CF care. For researchers, this study reinforces the need for longitudinal, ideally pre/post modulator studies with detailed muscle phenotyping — including imaging, biopsy, and metabolic testing — to determine whether and how CFTR correction at the molecular level translates to improved muscle biology over time.

Relevance: Cystic Fibrosis

Source: https://pubmed.ncbi.nlm.nih.gov/42674955/

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Kevin P Lonabaugh, HollyAnn Jacobs, Jordan Orofino et al.

Summary: A cross-sectional web-based survey of 97 adult females with cystic fibrosis across the United States and Canada examined contraceptive use patterns, knowledge, and preferences. Despite 90% of respondents not actively trying to conceive, only 55% reported using contraception, revealing a substantial gap between reproductive intent and protective behavior. Most participants (68%) wanted contraceptive guidance from their CF care team, yet fewer than 30% had actually received it. Persistent misconceptions about antibiotic-contraceptive interactions were also documented.

Why it matters: The dramatic improvement in CF survival and quality of life driven by CFTR modulators has transformed reproductive health from a theoretical concern into an immediate clinical priority. Unintended pregnancy in CF carries real risks: CFTR modulator teratogenicity data remain limited, disease burden complicates pregnancy management, and medication adjustments may be required. The finding that nearly half of sexually active women with CF who are not trying to conceive are nonetheless unprotected underscores an actionable gap in routine CF care. The documented misconception about antibiotics reducing contraceptive efficacy is a specific, correctable knowledge deficit that CF pharmacists and clinicians are well-positioned to address.

Expert perspective: This study contributes useful descriptive data to an underexplored area of CF care, but the evidence base has meaningful limitations that temper strong conclusions. The sample of 97 participants is modest, and recruitment through Community Voice and Elevate — online communities affiliated with the Cystic Fibrosis Foundation — introduces self-selection bias. Individuals who voluntarily join a virtual patient community and respond to a reproductive health survey are likely more engaged with their CF care and more comfortable discussing reproductive topics than the broader CF population, meaning the true counseling gap in the general CF population could be even wider than reported here.

The cross-sectional design captures a single point in time and cannot establish whether counseling deficits caused the gaps in contraceptive use, nor whether provider-initiated conversations actually change contraceptive behavior or outcomes. The survey was also limited to females aged 18 and older, so findings cannot be generalized to adolescents or to nonbinary and transgender individuals with CF who may also require contraceptive counseling.

The finding that side-effect profiles were valued more than contraceptive efficacy is clinically interesting and probably underappreciated in routine practice, suggesting that patient-centered contraceptive counseling in CF should lead with tolerability rather than effectiveness rankings. The antibiotic-contraceptive misconception finding deserves particular attention: current evidence does not support a clinically meaningful interaction between most antibiotics commonly used in CF and hormonal contraceptives (rifampin being the notable exception), and correcting this misconception is a concrete, low-cost intervention. CF pharmacists are ideally placed to deliver this counseling. The 28% rate of receiving contraceptive counseling from the CF team is low but not surprising; reproductive health has historically been siloed from CF disease management. This paper provides reasonable justification — even if preliminary — for incorporating standardized reproductive health discussions into CF care protocols, though the field will need larger, more representative studies and ultimately intervention trials to determine whether structured counseling programs translate into better reproductive health outcomes.

Relevance: Cystic Fibrosis

Source: https://pubmed.ncbi.nlm.nih.gov/42670820/

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Zihanjiao Wang, Rasa Ruseckaite, Aleksandar Dobric et al.

Summary: This scoping review systematically examined published literature from 2003–2025 on CFTR modulator use during pregnancy and the postpartum period in women with cystic fibrosis. The authors assessed maternal outcomes (lung function, nutritional status, complications) and fetal/neonatal outcomes (birth weight, congenital anomalies, neonatal complications) across all approved modulator regimens. The central finding is that elexacaftor/tezacaftor/ivacaftor (ETI) appears to confer maternal benefit, and inadvertent fetal exposure has not been clearly linked to serious adverse outcomes — but long-term data on exposed children and safety during lactation remain genuinely insufficient.

Why it matters: CFTR modulators, particularly ETI, have transformed the health trajectory of people with CF, enabling more women to survive into reproductive age and pursue pregnancy in substantially better health than prior generations. This creates an urgent and practical clinical question: should CFTR modulators be continued, modified, or discontinued during pregnancy and lactation? The answer carries real stakes — discontinuation risks maternal pulmonary decline, while continuation exposes a developing fetus and potentially a nursing infant to drugs whose long-term developmental effects are unknown. Clinicians and patients currently make these decisions with limited evidence, and this review maps the current state of that evidence base honestly.

Expert perspective: Scoping reviews are designed to characterize the landscape of available literature rather than to synthesize effect estimates, and this one performs that function appropriately. The review's value lies in what it reveals about the shape of the evidence gap rather than in generating new conclusions about safety or efficacy.

Most available data come from case series, registry cohorts, and pharmacovigilance reports — not randomized trials, which are neither feasible nor ethical in this context. Confounding by indication is pervasive and largely uncontrollable: women who continue ETI during pregnancy may differ systematically from those who discontinue, both in disease severity and in access to specialist care. Sample sizes across nearly all reviewed studies are small; ETI has only been widely available since 2019, and the reassuring neonatal outcomes reported to date reflect short follow-up windows and modest numbers. Rare teratogenic signals, neurodevelopmental effects, or metabolic consequences in exposed children cannot be excluded by the current evidence. Lactation safety remains particularly data-sparse, with drug concentrations in breast milk and their pharmacokinetic implications for nursing infants poorly characterized for most modulators.

The conclusion that ETI "may improve maternal health" is reasonable and consistent with the broader clinical literature, but extrapolating this benefit to pregnancy remains observational. The absence of a clear harm signal from fetal exposure is genuinely reassuring as a starting point, but absence of detected harm in small, short-term datasets is not equivalent to established safety — a distinction the authors draw responsibly.

The call for registry integration is well-founded. National and international CF registries — including the US Cystic Fibrosis Foundation Patient Registry and the European CF Society Patient Registry — are among the few instruments with the longitudinal reach and sample aggregation needed to study pregnancy outcomes at meaningful scale. Linkage of CF registry data to obstetric, neonatal, and pediatric developmental databases would substantially improve the evidence base, and harmonized data definitions and cross-registry collaboration could deliver insights that no single-centre study can achieve. The main unanswered questions — long-term neurodevelopmental and metabolic outcomes in ETI-exposed children, optimal dosing strategies during pregnancy, and lactation pharmacokinetics — will require coordinated registry infrastructure and prospective follow-up extending well beyond current data collection norms in CF research.

Relevance: Cystic Fibrosis | CF Registry and Real-World Evidence

Source: https://pubmed.ncbi.nlm.nih.gov/42778208/

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