Trials of GDNF in Parkinson's disease have yielded inconsistent results. In a randomised controlled trial, Whone et al. administer GDNF using a paradigm designed to optimize delivery to the putamen. ...18FDOPA PET reveals putamen-wide uptake, but GDNF does not differ from placebo in its effects on motor function.
Abstract
We investigated the effects of glial cell line-derived neurotrophic factor (GDNF) in Parkinson's disease, using intermittent intraputamenal convection-enhanced delivery via a skull-mounted transcutaneous port as a novel administration paradigm to potentially afford putamen-wide therapeutic delivery. This was a single-centre, randomized, double-blind, placebo-controlled trial. Patients were 35-75 years old, had motor symptoms for 5 or more years, and presented with moderate disease severity in the OFF state Hoehn and Yahr stage 2-3 and Unified Parkinson's Disease Rating Scale motor score (part III) (UPDRS-III) between 25 and 45 and motor fluctuations. Drug delivery devices were implanted and putamenal volume coverage was required to exceed a predefined threshold at a test infusion prior to randomization. Six pilot stage patients (randomization 2:1) and 35 primary stage patients (randomization 1:1) received bilateral intraputamenal infusions of GDNF (120 µg per putamen) or placebo every 4 weeks for 40 weeks. Efficacy analyses were based on the intention-to-treat principle and included all patients randomized. The primary outcome was the percentage change from baseline to Week 40 in the OFF state (UPDRS-III). The primary analysis was limited to primary stage patients, while further analyses included all patients from both study stages. The mean OFF state UPDRS motor score decreased by 17.3 ± 17.6% in the active group and 11.8 ± 15.8% in the placebo group (least squares mean difference: −4.9%, 95% CI: −16.9, 7.1, P = 0.41). Secondary endpoints did not show significant differences between the groups either. A post hoc analysis found nine (43%) patients in the active group but no placebo patients with a large clinically important motor improvement (≥10 points) in the OFF state (P = 0.0008). 18F-DOPA PET imaging demonstrated a significantly increased uptake throughout the putamen only in the active group, ranging from 25% (left anterior putamen; P = 0.0009) to 100% (both posterior putamina; P < 0.0001). GDNF appeared to be well tolerated and safe, and no drug-related serious adverse events were reported. The study did not meet its primary endpoint. 18F-DOPA imaging, however, suggested that intermittent convection-enhanced delivery of GDNF produced a putamen-wide tissue engagement effect, overcoming prior delivery limitations. Potential reasons for not proving clinical benefit at 40 weeks are discussed.
Intraputamenal glial cell line-derived neurotrophic factor (GDNF), administered every 4 weeks to patients with moderately advanced Parkinson's disease, did not show significant clinical improvements ...against placebo at 40 weeks, although it significantly increased 18FDOPA uptake throughout the entire putamen.
This open-label extension study explored the effects of continued (prior GDNF patients) or new (prior placebo patients) exposure to GDNF for another 40 weeks.
Using the infusion protocol of the parent study, all patients received GDNF without disclosing prior treatment allocations (GDNF or placebo). The primary outcome was the percentage change from baseline to Week 80 in the OFF state Unified Parkinson's Disease Rating Scale (UPDRS) motor score.
All 41 parent study participants were enrolled. The primary outcome decreased by 26.7±20.7% in patients on GDNF for 80 weeks (GDNF/GDNF; N = 21) and 27.6±23.6% in patients on placebo for 40 weeks followed by GDNF for 40 weeks (placebo/GDNF, N = 20; least squares mean difference: 0.4%, 95% CI: -13.9, 14.6, p = 0.96). Secondary endpoints did not show significant differences between the groups at Week 80 either. Prespecified comparisons between GDNF/GDNF at Week 80 and placebo/GDNF at Week 40 showed significant differences for mean OFF state UPDRS motor (-9.6±6.7 vs. -3.8±4.2 points, p = 0.0108) and activities of daily living score (-6.9±5.5 vs. -1.0±3.7 points, p = 0.0003). No treatment-emergent safety concerns were identified.
The aggregate study results, from the parent and open-label extension suggest that future testing with GDNF will likely require an 80- rather than a 40-week randomized treatment period and/or a higher dose.
In the United States, medically underserved women carry a heavier burden of cancer incidence and mortality, yet are largely underrepresented in cancer prevention studies. My Body, My Test is a n ...observational cohort, multi-phase cervical cancer prevention study in North Carolina that recruited low-income women, aged 30-65 years and who had not undergone Pap testing in ≥ 4 years. Participants were offered home-based self-collection of cervico-vaginal samples for primary HPV testing. Here, we aimed to describe the recruitment strategies utilized by study staff, and the resulting recruitment and self-collection kit return rates for each specific recruitment strategy. Participants were recruited through different approaches: either direct (active, staff-effort intensive) or indirect (passive on the part of study staff). Of a total of 1,475 individuals screened for eligibility, 695 were eligible (47.1%) and 487 (70% of eligible) participants returned their self-collection kit. Small media recruitment resulted in the highest number of individuals found to be study eligible, with a relatively high self-collection kit return of 70%. In-clinic in-reach resulted in a lower number of study-eligible women, yet had the highest kit return rate (90%) among those sent kits. In contrast, 211 recruitment which resulted in the lowest kit return of 54%. Small media, word of mouth, and face-to-face outreach resulted in self-collection kit return rates ranging from 72 to 79%. The recruitment strategies undertaken by study staff support the continued study of reaching under-screened populations into cervical cancer prevention studies.
Under-screened women are more likely to be diagnosed with invasive cervical cancer at later stages and have worse survival outcomes. Under- or un-insured women, low-income women, and minoritized ...groups face barriers to screening. Intention to screen is an indicator of future screening behavior, yet is understudied among low-income, under-screened women. Participants were 710 low-income, uninsured or publicly insured women ages 25–64 years in North Carolina who were not up to date on cervical cancer screening according to national guidelines. Participants were asked about barriers to screening and intention to screen. We estimated reported barriers to cervical cancer screening stratified by race and ethnicity (categorized as White, Black, and Hispanic) and assessed predictors of intention to screen. Sixty-one percent of all participants reported 5 or more barriers to screening. The most commonly reported reasons for not getting screened were lack of insurance (White: 71%, Black: 62%, Hispanic/Latina: 63%) and cost (White: 55%, Black: 44%, Hispanic/Latina: 61%). Women were more likely to have an intention to screen if they reported “it was not hard to get screening” (OR: 1.47 (1.00, 2.15)). Older women reported being less likely to intend to screen. Black women reported being more likely to intend to screen than White women. Lack of health insurance and cost were frequently reported barriers to cervical cancer screening. Increasing knowledge of affordable clinics and expanding access to Medicaid may reduce barriers and increase cervical cancer screening uptake.
To evaluate the validity and acceptability of at-home self-collection to test for high-risk human papillomavirus (HPV) and sexually transmitted infections among women overdue for cervical cancer ...screening by national guidelines.
Low-income, infrequently screened women were recruited from the general population in North Carolina to participate in an observational study. Participants provided two self-collected cervicovaginal samples (one at home and one in the clinic) and a clinician-collected cervical sample. Samples were tested for high-risk HPV, Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and Mycoplasma genitalium. Cervical samples were also tested by liquid-based cytology.
Overall, 193 women had conclusive high-risk HPV results for all three samples and cytology results. Prevalence of high-risk HPV within self-home samples (12.4%) was not different from that within clinician samples (11.4%; P=.79) and from that within self clinic samples (15.5%; P=.21). Positivity for high-risk HPV in all sample types increased with increasing grades of cervical abnormality (P<.001). Self-home samples detected high-risk HPV in all identified cases of high-grade squamous intraepithelial lesions and of cervical intraepithelial neoplasia 2 or worse. Detection was comparable across sample types for T vaginalis (range 10.2-10.8%), M genitalium (3.3-5.5%), C trachomatis (1.1-2.1%), and N gonorrhoeae (0-0.5%). Kappa values between sample types ranged from 0.56 to 0.66 for high-risk HPV, 0.86-0.91 for T vaginalis, and 0.65-0.83 for M genitalium. Most participants reported no difficulty understanding self-collection instructions (93.6%) and were willing to use self-collection in the future (96.3%).
Mail-based, at-home self-collection for high-risk HPV and sexually transmitted infection detection was valid and well accepted among infrequently screened women in our study. These findings support the future use of high-risk HPV self-collection to increase cervical cancer screening rates among higher risk women in the United States.
Self-collection of cervico-vaginal samples for human papillomavirus (HPV) testing has the potential to make cervical cancer screening more accessible to underscreened women. We evaluated the ...acceptability and ease of use of home-based HPV self-collection within a diverse population of low-income, infrequently screened women.
Participants were low-income women from North Carolina who had not received Pap testing in 4 or more years. Eligible women received a self-collection kit containing instructions and a brush for home-based sample collection. A total of 227 women returned a self-collected sample by mail and completed a questionnaire to assess their experiences with HPV self-collection. We described acceptability measures and used logistic regression to identify predictors of overall positive thoughts about the self-collection experience.
Nearly all women were willing to perform HPV self-collection again (98%) and were comfortable receiving the self-collection kit in the mail (99%). Overall, 81% of participants reported positive thoughts about home-based self-collection. Women with at least some college education and those who were divorced, separated or widowed were more likely to report overall positive thoughts. Aspects of self-collection that participants most commonly reported liking included convenience (53%), ease of use (32%) and privacy (23%). The most frequently reported difficulties included uncertainty that the self-collection was done correctly (16%) and difficulty inserting the self-collection brush (16%).
Home-based self-collection for HPV was a highly acceptable screening method among low-income, underscreened women and holds the promise to increase access to cervical cancer screening in this high-risk population.
We sought to examine cervical cancer screening barriers by sexual orientation among low-income women in North Carolina. The MyBodyMyTest-3 Trial recruited low-income women (< 250% of federal poverty ...level) aged 25–64 years who were 1+ year overdue for cervical cancer screening. We compared perceptions of cervical cancer screening among those who self-identified as lesbian, gay, bisexual, or queer (LGBQ;
n
= 70) to straight/heterosexual women (
n
= 683). For both LGBQ and straight respondents, the greatest barriers to screening were lack of health insurance (63% and 66%) and cost (49% and 50%). LGBQ respondents were more likely than straight respondents to report forgetting to screen (16% vs. 8%,
p
= .05), transportation barriers (10% vs. 2%,
p
= .001), and competing mental or physical health problems (39% vs. 27%,
p
= .10). Addressing access remains important for improving cervical cancer screening among those under-screened. For LGBQ women, additional attention may be needed for reminders, co-occurring health needs, and transportation barriers.
Underscreened, low-income, and uninsured or publicly insured women in the United States bear a greater burden of cervical cancer morbidity and mortality and may face unique barriers that preclude ...screening adherence.
Participants were 710 My Body My Test-3 clinical trial participants who were publicly insured or uninsured with incomes ≤250% of the U.S. Federal Poverty Level, aged 25-64 years, and not up to date on cervical cancer screening as per national guidelines. Using Health Belief Model constructs, we assessed screening-related knowledge, perceptions, and behaviors-overall and stratified by race and ethnicity-and estimated associations with past-year attempted screening using multivariable regression models.
Overall, knowledge was low about the human papillomavirus, purpose of a Pap test, and recommended screening interval. Perceived severity of cervical cancer was high (3.63 on a 4-point scale). Black and Latina/Hispanic women were more likely to perceive screening as lowering their risk of cervical cancer than White women. Black women reported lower perceived risk of cervical cancer compared with White women (
= 0.03), but Black women were more likely to have sought screening in the past year (
= 0.01). Having at least three doctor visits in the past year was associated with a screening attempt. Greater perceived risk of cervical cancer, more positive perceptions of screening, and feeling more nervousness about screening were also associated with a screening attempt (all
< 0.05).
Addressing knowledge gaps and misconceptions about cervical cancer screening and leveraging positive perceptions of screening may improve screening uptake and adherence among diverse underscreened U.S. women. Clinical Trial Registration Number: NCT02651883.
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