Safety and Efficacy of Drug Holidays for Women with Sexual Dysfunction Induced by Selective Serotonin Reuptake Inhibitors (SSRIs) Other than Fluoxetine: An Open-Label Randomized Clinical Trial

Selective serotonin reuptake inhibitors (SSRIs) are the cornerstone of psychopharmacology. However, they cause side effects such as sexual dysfunction, leading to the discontinuation of treatment. We aimed to investigate the efficacy and safety of drug holidays for women experiencing sexual dysfunction Induced by SSRIs other than fluoxetine. This study was an 8-week randomized, open-label, controlled trial including married women aged between 18 and 50 years who had experienced sexual dysfunction while undergoing treatment with SSRIs. The intervention group implemented drug holidays by not taking medications on Thursdays and Fridays, while the control group continued regular medication use. The female sexual function index (FSFI) and the 28-question general health questionnaire (GHQ-28) were administered to assess sexual function and mental health, respectively. A total of 50 participants completed the trial. The drug holidays' group showed significant improvements in arousal (p < 0.001), desire (p = 0.001), orgasm (p < 0.001), satisfaction (p < 0.001), lubrication (p = 0.021), and overall sexual health (p < 0.001). The between-group difference of pain was significant (p < 0.001), despite no significant within-group change. Mental health improved in both groups, despite no significant between-group difference. No major adverse effects were reported. Drug holidays did not introduce immediate safety concerns or significant adverse effects during the timeframe of eight weeks, suggesting that it may be a safe and effective strategy for managing SSRI-induced sexual dysfunction in women, alongside improving mental health. Further research is needed to reach a definitive conclusion.

A nested case-control study of factors contributing to the development of medication-related osteonecrosis of the jaw in patients using bone resorption inhibitors in Mishima City

PURPOSE

Medication-related osteonecrosis of the jaw (MRONJ) is characterized by necrosis of the jawbone with intraoral bacterial infection and has a significant negative impact on oral health-related quality of life. Risk factors for the onset are unknown, and definitive therapeutic approaches have not yet been defined. A case-control study at a single institution in Mishima City was conducted. The purpose of this study was to examine in detail the factors that contribute to the development of MRONJ.

METHODS

Medical records of MRONJ patients who visited Mishima Dental Center, Nihon University School of Dentistry, during the period 2015-2021 were extracted. Counter-matched sampling design was used to select participants matched for sex, age, and smoking for this nested case-control study. The incidence factors were statistically examined by logistic regression analysis.

RESULTS

Twelve MRONJ patients were used as cases and 32 controls were matched. After adjustment for potential confounders, injectable bisphosphonates (aOR = 24.5; 95% CI = 1.05, 575.0; P < 0.05) were significantly associated with the development of MRONJ.

CONCLUSION

High-dose bisphosphonates may be a risk factor for the development of MRONJ. Patients who use these products require careful prophylactic dental treatment against inflammatory diseases, and dentists and physicians should maintain close communication.

Global Dynamics of SARS-CoV-2 Infection with Antibody Response and the Impact of Impulsive Drug Therapy

Mathematical modeling is crucial to investigating tthe ongoing coronavirus disease 2019 (COVID-19) pandemic. The primary target area of the SARS-CoV-2 virus is epithelial cells in the human lower respiratory tract. During this viral infection, infected cells can activate innate and adaptive immune responses to viral infection. Immune response in COVID-19 infection can lead to longer recovery time and more severe secondary complications. We formulate a micro-level mathematical model by incorporating a saturation term for SARS-CoV-2-infected epithelial cell loss reliant on infected cell levels. Forward and backward bifurcation between disease-free and endemic equilibrium points have been analyzed. Global stability of both disease-free and endemic equilibrium is provided. We have seen that the disease-free equilibrium is globally stable for R0<1, and endemic equilibrium exists and is globally stable for R0>1. Impulsive application of drug dosing has been applied for the treatment of COVID-19 patients. Additionally, the dynamics of the impulsive system are discussed when a patient takes drug holidays. Numerical simulations support the analytical findings and the dynamical regimes in the systems.

Drug Holidays and Overall Survival of Patients with Metastatic Colorectal Cancer

Different de-escalation strategies have been proposed to limit the risk of cumulative toxicity and guarantee quality of life during the treatment trajectory of patients with metastatic colorectal cancer (mCRC). Programmed treatment interruptions, defined as drug holidays (DHs), have been implemented in clinical practice. We evaluated the association between DHs and overall survival (OS). This was a retrospective study, conducted at the University Hospital of Udine and the IRCCS CRO of Aviano. We retrieved records of 608 consecutive patients treated for mCRC from 1 January 2005 to 15 March 2017 and evaluated the impact of different de-escalation strategies (maintenance, DHs, or both) on OS through uni- and multivariate Cox regression analyses. We also looked at attrition rates across treatment lines according to the chosen strategy. In our study, 19.24% of patients received maintenance therapy, 16.12% DHs, and 9.87% both, while 32.07% continued full-intensity first-line treatment up to progression or death. In uni- and multivariate analyses first-line continuous treatment and early discontinuation (treatment for less than 3 months) were associated to worse OS compared to non-continuous strategies (HR, 1.68; 95% CI, 1.22-2.32; p = 0.002 and HR,4.89; 95% CI, 3.33-7.19; p < 0.001, respectively). Attrition rates were 22.8%, 20.61%, and 19.64% for maintenance, DHs, or both, respectively. For continuous therapy and for treatment of less than 3 months it was 21.57% and 49%. De-escalation strategies are safe and effective options. DHs after initial induction chemotherapy may be considered in clinically selected patients with metastatic colorectal cancer.

ADHD and Drug Holidays: Effects on Anthropometric Changes during Methylpenidate Treatment

OBJECTIVES

The current study evaluated the long-term effects of methylphenidate (MPH) discontinuation on growth parameters in Turkish children and adolescents with attention-deficit/hyperactivity disorder (ADHD).

EXPERIMENTAL DESIGN

432 children and adolescents (aged 6-18 years) with ADHD receiving MPH for at least 1 year between March 2012 and January 2019 were included in a retrospective cohort study. We analyzed weight, height, and body mass index (BMI) standard deviation z scores (SDS) of groups that either did (ADHD-C) or did not (ADHD-DC) discontinue MPH. Growth parameters were converted to z scores as normative values for the Turkish population to compare the measurements at baseline and the last follow-up visit by using the paired sample t-test.

PRINCIPAL OBSERVATIONS

In patients from the ADHD-C group, statistically significant negative correlations were found between age at starting MPH and differences in weight and height SDS between baseline and follow-up. Children had a greater reduction in weight and height compared to adolescents. When we evaluated the differences in pre-and post-treatment growth factors, we found no significant differences between the groups in terms of growth parameters.

CONCLUSIONS

Our data showed that chronic use of MPH was likely responsible for changes in height and weight parameters.

Determinants of choice in offering drug holidays during first-line therapy for metastatic colorectal cancer

Background: 'Drug holidays' (DH) for metastatic colorectal cancer (mCRC) were introduced to preserve quality of life. We studied factors associated to a DH offer in first line. Materials & methods: We retrospectively analyzed 754 consecutive patients treated with chemotherapy for mCRC in two Italian institutions between 2005 and 2017. Associations between baseline clinical-pathological factors and DH (56 or more days of treatment interruption) were investigated. Results: In 754 patients, previous metastasectomy, previous thermoablation and previous surgery of primary tumor were independently associated with DH. Excluding procedures or clinical trials: primary rectal cancer and resection of primary tumor were significantly associated to DH. Conclusions: DH was offered to patients with lower burden of disease, but further investigations are needed to safely guide a holiday strategy.

Effects of a Proactive Interdisciplinary Self-Management (PRISMA) program on medication adherence in patients with type 2 diabetes in primary care: a randomized controlled trial

PURPOSE

The present study aims to investigate the effect of the group-based Proactive Interdisciplinary Self-Management (PRISMA) training program on medication adherence in patients with type 2 diabetes (T2DM) treated in primary care.

PATIENTS AND METHODS

The current study is a two-arm, parallel group, randomized, open label trial (1:1) of 6-month duration with a 6-month extension period in which both groups received the intervention (wait-list control). People 18 years old or older who were diagnosed with T2DM were included. The intervention consisted of two group meetings about T2DM guided by care providers. The control group received usual care only (visits at the general practice). The primary outcome was adherence based on pharmacy refill data and was measured using medication possession ratio (MPR). The secondary outcomes were the number of drug holidays and self-reported adherence, measured by the 5-item Medication Adherence Rating Scale (MARS-5).

RESULTS

Of the total sample (n=108), 66.6% were male. The mean age was 69.3 years (SD=9.1). In the 6-month period, patients were more adherent in the intervention group (n=56) (median MPR =100.0 [51.1-100.0]) than in the control group (n=52) (median MPR =97.7 [54.1-100.0]) (U=1,042, z=-2.783, P=0.005). The intervention group had less drug holidays than the control group (relative risk 0.55, 95% CI, 0.37-0.80). The sum scores of the MARS did not differ between the intervention group (median =23.98, SD=0.91) and the control group (median =24.00, SD=1.54).

CONCLUSION

The PRISMA program resulted in a small improvement in MPR and fewer drug holidays, while no improvement has been found in self-reported adherence. However, health care providers and policy makers could take into account that adherence might be influenced by PRISMA.

Resistance to Taxanes in Triple-Negative Breast Cancer Associates with the Dynamics of a CD49f+ Tumor-Initiating Population

Taxanes are a mainstay of treatment for breast cancer, but resistance often develops followed by metastatic disease and mortality. Aiming to reveal the mechanisms underlying taxane resistance, we used breast cancer patient-derived orthoxenografts (PDX). Mimicking clinical behavior, triple-negative breast tumors (TNBCs) from PDX models were more sensitive to docetaxel than luminal tumors, but they progressively acquired resistance upon continuous drug administration. Mechanistically, we found that a CD49f+ chemoresistant population with tumor-initiating ability is present in sensitive tumors and expands during the acquisition of drug resistance. In the absence of the drug, the resistant CD49f+ population shrinks and taxane sensitivity is restored. We describe a transcriptional signature of resistance, predictive of recurrent disease after chemotherapy in TNBC. Together, these findings identify a CD49f+ population enriched in tumor-initiating ability and chemoresistance properties and evidence a drug holiday effect on the acquired resistance to docetaxel in triple-negative breast cancer.

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PDX models mimic the clinical response to docetaxel in breast cancer patients

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Sensitivity to docetaxel can be regained in metastatic resistant TNBC

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A tumor-initiating CD49f chemoresistant population is present in TNBC

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Docetaxel resistance associates with the expansion of a CD49f+ population in TNBC

Addressing Adherence Using Genotype-Specific PBPK Modeling-Impact of Drug Holidays on Tamoxifen and Endoxifen Plasma Levels

Introduction: Tamoxifen is one of the most common treatment opportunities for hormonal positive breast cancer. Despite its good tolerability, patients demonstrate decreasing adherence over years impacting on therapeutic success. PBPK modeling was applied to demonstrate the impact of drug holidays on plasma levels of tamoxifen and its active metabolite endoxifen for different CYP2D6 genotypes.

Materials and Methods: A virtual study with 24,000 patients was conducted in order to investigate the development of tamoxifen steady-state kinetics in patient groups of different CYP2D6 genotypes. The impact of drug holidays on steady-state kinetics was investigated assuming changing drug holiday scenarios.

Results: Drug holidays in CYP2D6 extensive and intermediate metabolizers (EMs, IMs) exceeding 1 month lead to a decrease of endoxifen steady-state trough levels below the 5th percentile of the control group. Assuming drug holidays of 1, 2, or 3 months and administering a fixed-dose combination of 20 mg tamoxifen and 3 mg endoxifen EMs demonstrated re-established endoxifen steady-state trough levels after 5, 8, and 9 days. IMs receiving the same fixed-dose combination demonstrated re-established endoxifen steady-state trough levels after 7, 10, and 11 days.

Discussion: The PBPK model impressively demonstrates the impact of drug holidays in different CYP2D6 genotypes on PK. Population simulation results indicate that drug holidays of more than 2 weeks cause a tremendous decrease of plasma levels despite the long half-life of tamoxifen. To improve therapeutic success, PBPK modeling allows identifying genotype-specific differences in PK following drug holidays and adequate treatment with loading doses.

Patterns of Non-adherence to Supplementation with Calcium and Vitamin D in Persistent Postmenopausal Women Are Similar at Start and 1 Year Later: A Qualitative Longitudinal Study

Background: Osteoporosis is a chronic disease and adherence can fluctuate over time. Therefore, longer observation is necessary to investigate the stability of patients' adherence. The study aim was to compare the overall adherence (OA) to supplementation with the fixed combination of calcium and vitamin D (Ca/D) in postmenopausal women at baseline and after 1 year, and to evaluate the fluctuation of the OA in individual months. Furthermore, we studied whether adherence is influenced by signing of informed consent and routine medical check-up.

Methods: This was a longitudinal, observational study. The data were obtained from the Osteocenter of University Hospital in Hradec Kralove, Czech Republic. Adherence was measured using electronic bottles type Medication Events Monitoring System (MEMS). The study was carried out in two 3-month periods; the baseline in 2013 (signing of informed consent while medical check-up) and the follow-up (medical check-up) in 2014. The adherence and adherence-related outcomes were studied in patients who had initiated osteoporosis treatment and were persistent.

Results: 21 (49%) out of 43 patients who avoided drug dispenser and were persistent both at baseline and at follow-up, completed the study and were included. Median age was 76. Evaluating the whole 3-month periods, the OA did not differ significantly at baseline and at follow-up, the OA was 71 and 68%, respectively. However, the adherence in month 1 at baseline was significantly higher than the adherence in month 2 at baseline (p < 0.001) and also than the adherence in month 1 at follow-up (p = 0.010). Analysing the study period without month 1, a stable adherence was observed in 48% of patients. About 33% of doses were omitted at baseline and 34% at follow-up. As many as 71% of the patients took drug holidays at baseline, and 76% at follow-up.

Conclusion: The OA was insufficient, around 70% both at baseline and at follow-up. One half of the patients showed a stable adherence. The patterns of non-adherence were very similar at follow-up. Signing of the informed consent seems to act as bias more than regular medical check-up.

Drug holidays: the most frequent type of noncompliance with calcium plus vitamin D supplementation in persistent patients with osteoporosis

PURPOSE

All current recommendations include calcium and vitamin D (Ca-D) as an integrated part of osteoporosis treatment. The purpose of this pilot study was to analyze compliance with a fixed combination of Ca-D in women persistent with the treatment.

PATIENTS AND METHODS

An observational study was carried out in three osteocenters in the Czech Republic. Women with osteoporosis ≥55 years of age concurrently treated with oral ibandronate were eligible. Compliance was evaluated in a period of 3 months by Medication Event Monitoring System (MEMS), tablet count, and self-report. Nonpersistence was defined as a MEMS-based gap in the use of Ca-D to be 30 days or more.

RESULTS

A total of 73 patients were monitored, of which 49 patients were analyzed (target population). Based on MEMS, mean overall compliance was 71%; good compliance (≥80%) was observed in 59% of the patients. As many as 71% of the patients took drug holidays (≥3 consecutive days without intake); overall compliance of these patients was 59% and was slightly lower on Fridays and weekends. Patients without drug holidays were fully compliant (did not omit individual doses). Compliance differed according to daily time at which the patients mostly used the Ca-D. Afternoon/evening takers showed a mean overall compliance of 82% while morning/night takers only 51% (P=0.049). Based on MEMS, tablet count, and self-report, compliance ≥75% was observed in 59%, 100%, and 87% of the patients, respectively. Outcomes obtained by the three methods were not associated with each other. Undesirable concurrent ingestion of Ca-D and ibandronate was present only twice.

CONCLUSION

Despite almost perfect self-reported and tablet count-based compliance, MEMS-based compliance was relatively poor. Consecutive supplementation-free days were common; more than two-thirds of the patients took at least one drug holiday. This pilot study showed drug holiday to be the most important type of noncompliance with Ca-D in those who are persistent with the treatment.

Bisphosphonate drug holidays: Can we recommend currently?

Bisphosphonates (BP) are the mainstay of treatment for osteoporosis. Subtrochanteric or diaphyseal fractures have been reported with long term use of BP, which raised world-wide debate on two aspects, i.e., for how long the BP is to be given and potential advantages/role of BP drug holidays. BP accumulates in bone with some persistent protective effect after therapy is stopped endorses the concept. Theoretically, a drug holiday may be a considerable option to decrease risks of BP, which continuing the protection from fractures but the level of evidence and data supporting the concept of drug holidays is a week. Hence, no specific recommendations are available on BP drug holidays from major available treatment guidelines on postmenopausal osteoporosis. Hence, before it is recommended it requires more robust research in this field.

Bridging, switching or drug holidays - how to treat a patient who stops natalizumab?

Natalizumab (NAT) was the first monoclonal antibody to be approved for the treatment of relapsing-remitting multiple sclerosis (RRMS). While pivotal and postmarketing studies have showed considerable and sustained efficacy of NAT in RRMS, the increasing incidence of therapy-associated progressive multifocal leukoencephalopathy (PML), a brain infection caused by the John Cunningham virus (JCV), is a risk associated with long-term therapy. The risk for therapy-associated PML is highest in so-called “triple risk” patients. Therefore, long-term NAT-treated, immunosuppressive-pretreated, and JCV antibody-positive patients often discontinue NAT therapy. However, until now, it is not known which treatment strategy should be followed after NAT cessation. Since disease activity returns to pretreatment levels, or even above, within 4–7 months from the last infusion of NAT, patients who stop NAT are at considerable risk of relapse and worsening of multiple sclerosis (MS)-related disability. Several strategies have been applied to prevent the recurrence of disease activity after discontinuation of NAT. Of these, bridging with intravenous methylprednisolone, and switching to glatiramer acetate or interferon beta (IFN-beta) do not seem to be effective enough. More promising results have been obtained in retrospective studies and case series with fingolimod (FTY), an alternative escalation therapy for RRMS, although some patients have showed a severe disease rebound after starting FTY treatment. The time interval between the discontinuation of NAT and the start of FTY might affect the recurrence of disease activity. Long-term data about the efficacy and safety of FTY treatment after cessation of NAT are urgently needed and should be further investigated. Prospective studies are warranted, to optimize treatment strategies for RRMS patients who discontinue NAT, especially because new therapies will be available in the very near future.

Bisphosphonate drug holiday: who, when and how long

Bisphosphonates have been widely used in the treatment of osteoporosis with robust data from numerous placebo-controlled trials demonstrating efficacy in fracture risk reduction over 3-5 years of treatment. Although bisphosphonates are generally safe and well tolerated, concerns have emerged about adverse effects related to long-term use. For most patients with osteoporosis, the benefits of treatment outweigh the risks. Because these agents accumulate in bone with some persistent antifracture efficacy after therapy is stopped, it is reasonable to consider a 'drug holiday.' There is considerable controversy regarding the optimal duration of therapy and the length of the holiday, both of which should be based on individual assessments of risk and benefit.