Primary Care Guidance for Providers of Care for Persons With Human Immunodeficiency Virus: 2024 Update by the HIV Medicine Association of the Infectious Diseases Society of America.

Advances in antiretroviral therapy (ART) have made it possible for persons with human immunodeficiency virus (HIV) to live a lifespan approaching that of people without HIV, without progressing to AIDS or transmitting HIV to sexual partners or infants. There is, therefore, increasing emphasis on maintaining health throughout the lifespan. To receive optimal medical care and achieve desired outcomes, persons with HIV must be consistently engaged in care and able to access uninterrupted treatment, including ART. Comprehensive evidence-based HIV primary care guidance is, therefore, more important than ever. Creating a patient-centered, stigma-free care environment is essential for care engagement. Barriers to care must be decreased at the societal, health system, clinic, and individual levels. As the population ages and noncommunicable diseases arise, providing comprehensive health care for persons with HIV becomes increasingly complex, including management of multiple comorbidities and the associated challenges of polypharmacy, while also attending to HIV-specific health concerns. Clinicians must address issues specific to preventive health, including cancer screening, providing recommended vaccinations, as well as promoting sexual health, including sexually transmitted infection diagnosis, treatment, and prevention. Clinicians also must address issues for specific populations, including persons of childbearing potential, including during preconception and pregnancy; children; adolescents; and transgender and gender-diverse individuals. This guidance from an expert panel of the HIV Medicine Association of the Infectious Diseases Society of America updates the previous 2020 HIV Primary Care Guidance.

Increase in Cases of Perinatal HIV Transmission in Maryland in 2022.

The perinatal transmission of HIV is preventable through a regimen that includes testing of all pregnant individuals, antiretroviral treatment (ART) for the pregnant individual, prophylactic or preventative ART for the infant, and cesarean section delivery for mothers with HIV viremia at the time of delivery. Under this protocol, the United States has seen a significant decline in the perinatal transmission of HIV and achieved a perinatal HIV transmission rate of 0.9% in 2019. However, despite this progress nationally and after zero transmissions in 2021, Maryland recorded 6 cases of perinatal HIV diagnoses in 2022. Each of the 3 major referral centers for pediatric HIV patients in Maryland reported 2 new cases in 2022. A root cause analysis of the cases identified risk factors including delayed entry into perinatal and HIV care, premature birth, maternal adherence challenges in the setting of substance use and other adverse social determinants of health, and failure to diagnose maternal HIV infection in a timely way. All patients were successfully linked to care and initiated on ART. Multiple factors contributed to the 2022 increase in cases of perinatal HIV in Maryland. To achieve and then sustain the elimination of perinatal HIV transmission, the constancy of systems that eliminate barriers for all pregnant people to access testing, prevention, and treatment is critical.

Follow-Up Outcomes of Children, Adolescents, and Young People on Darunavir-Based Third-Line Antiretroviral Therapy: Observational Cohort From 9 African Countries.

BACKGROUND: We assessed clinical outcomes among children, adolescents, and people younger than 25 years on darunavir-based antiretroviral therapy (ART) in 9 sub-Saharan African countries. SETTING: Third-line ART centers in Cameroon, Eswatini, Kenya, Lesotho, Nigeria, Rwanda, Uganda, Zambia, and Zimbabwe. METHODS: From January 2019 to December 2022, we collected data from a cohort of children, adolescents, and young people receiving third-line ART from 9 sub-Saharan African countries. Data on treatment continuity, viral suppression, death, and clinic transfers were extracted from medical records and summarized. Cox proportional hazards models were used to identify factors independently associated with retention in care. RESULTS: Of 871 participants enrolled, the median age was 14.8 (range: 0.2-24.7) years and 488 (56.0%) were male; 809 (92.9%) [median duration of follow-up of 28.3 months (interquartile range: 17.5-45.2)] had final outcomes after initiating third-line ART. Of these, 711 (87.9%) were alive and in care at the end of study follow-up, 29 (3.6%) died, 30 (3.7%) were transferred to other facilities, and 39 (4.8%) were lost to follow-up. Retention in care was less likely among male patients compared with female patients [aHR: 0.85, 95% confidence interval: 0.72 to 1.0] and in 10-14-year-old children compared with younger children. Adolescents (15-19 years old) had higher mortality compared with children younger than 10 years (aSHR: 4.20, 95% confidence interval: 1.37 to 12.87). Viral suppression was seen in 345/433 (79.7%), 249/320 (77.8%), and 546/674 (81.0%) patients with results at 6 months, 12 months, and study end, respectively. CONCLUSIONS: A high proportion of children and young people receiving third-line ART in sub-Saharan Africa remain in care and attain viral suppression during follow-up.

Progress in Eliminating Perinatal HIV Transmission in the Metropolitan DC Area Between 2018-2022.

BACKGROUND: The number of perinatal HIV cases have continued to decline since the United States achieved the goal of perinatal HIV elimination in 2019. We aimed to evaluate dynamics in perinatal HIV transmission in the metropolitan District of Columbia (DC) area during 2018-2022. SETTING: Children's National Hospital's (CNH) is a major referral site for the metropolitan DC area, including suburban Maryland and Virginia, and evaluates >95% of HIV-exposed infants (HEI) in the region. METHODS: A retrospective cohort study of mother-infant pairs with perinatal HIV exposure seen at CNH during 2018-2022. We describe the demographics, intrapartum/postpartum management, and outcomes among mothers and HEI. RESULTS: We analyzed 503 HEI; most (78.9%) were at low risk for perinatal HIV. Most mothers were African or African American (87.1%) and had HIV RNA <50 copies/mL around delivery (78.1%). The proportion of HEI at high risk for perinatal HIV decreased from 28.2% to 15.5% in 2018 and 2020, respectively, but increased to 24.8% in 2022. Most HEI received postnatal antiretroviral drugs for at least 4 weeks (95.3%). Seventy-nine infants (15.7%) were born to mothers diagnosed with HIV during pregnancy. Two infants (0.4%) were diagnosed with perinatally acquired HIV. CONCLUSIONS: We report high rates of antiretroviral drugs use among mother-infant pairs and a low rate of perinatal HIV transmission in metropolitan DC. Despite a 1.8-fold decrease in the number of high-risk perinatal HIV exposures since 2018, this rate rebounded in 2022. There remain opportunities to optimize maternal care and reduce the number of high-risk HEI.

Adolescents and young adults with HIV and unsuppressed viral load: where do we go from here?

PURPOSE OF REVIEW: Adolescents and youth living with HIV (AYLHIV) have worse outcomes at all stages of the care cascade when compared with adults, yet adolescents and youth with unsuppressed viral load are typically excluded from phase 3 studies of novel HIV therapeutic agents and emerging strategies. Long-acting agents have the potential to radically change outcomes for young people struggling with adherence to daily oral HIV medications. RECENT FINDINGS: 1.5 million children aged less than 15 years live with HIV and more than 100 000 acquire HIV perinatally every year. Adolescents and youth aged 10-24 years comprise ∼40% of global incident HIV infections. Rates of viral suppression among AYLHIV vary markedly from 44 to 88%, resulting in morbidity and risks of transmission to partners and infants. Virological failure is mostly due to poor adherence, and AYLHIV express high levels of interest and acceptability of alternatives to oral daily medications, such as long-acting antiretroviral formulations. Emerging data regarding their use in populations with unsuppressed viral load are encouraging. SUMMARY: AYLHIV, including populations without virologic suppression, must be prioritized for the programmatic implementation and research of long-acting HIV drugs and other therapeutic strategies to prevent morbidity and mortality and to ultimately end the HIV epidemic.

Cognitive impairment in children and adolescents living with perinatal HIV disease in the ART era: a meta-analysis.

Background: Despite improved survival and overall health outcomes from modern antiretroviral therapy (ART), children and adolescents living with HIV are facing pervasive impairments in neurodevelopment including cognitive impairment, but there remains a lack of consensus on the cognitive domains that are affected in those children and adolescents. The objective of this meta-analysis was to evaluate the impact of perinatal HIV-infection on executive function, working memory, and speed of information processing in the ART era. Methods: The PubMed database was searched for studies published between 1997 and 2024, plus additional search with the ScienceDirect, bioRxiv, and medRxiv databases. A meta-analysis was conducted on thirty-five studies published between 2012 and 2023 that encompassed a total of 4066 perinatally-infected HIV patients, 2349 HIV-exposed uninfected (HEU) controls, and 2466 HIV-unexposed, uninfected (HUU) controls. Performance scores on executive function, working memory, and processing speed were pooled using random-effects meta-analysis. Findings: Compared to HEU and HUU controls, perinatally HIV-infected children and adolescents presented with significant impairments in processing speed (Hedges g = -0.64, p < 0.00001), working memory (Hedges g = -0.69, p < 0.00001), and to a lesser degree, executive function (Hedges g = -0.35, p = 0.02). Meta-regression analysis suggested that the effect estimate of processing speed impairment negatively correlated with Gross National Income (GNI) per capita of the study countries (CALHIV vs HUU, p = 0.0016; CALHIV vs HEU, p = 0.0019), even though HIV-infected cases were compared to sociodemographically matched HUU controls from the same countries. Sub-group meta-analyses with participants from high-income or low-/middle-income countries provided further evidence suggesting that the performance gap between HIV-infected cases and HUU/HEU controls may be larger in low-/middle-income countries than high-income countries. Interpretation: In the ART era, cognitive impairment (especially reduced processing speed and working memory) persists in children and adolescents living with HIV. These impairments may be more pronounced among those children and adolescents living with HIV in low-income countries, suggesting that there may be global health inequities in treatment outcomes with perinatal HIV-infection. However, meta-analysis and meta-regression analysis have their limitations, which calls for future collaborative multi-country international studies to directly investigate this important topic. Nevertheless, there is an unmet need to assure equity in timely assessments and interventions to optimize neurocognitive development and outcomes among children and adolescents with perinatal HIV globally. Funding: This research was supported in part by NIH R01MH108466, NIH R56NS124422, and NIH R01NS124422.

Successful management of haemophagocytic lymphohistiocytosis in an adolescent with newly diagnosed HIV/AIDS and histoplasmosis.

Haemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening hyperinflammatory syndrome characterised by persistent fevers, cytopenia, hepatosplenomegaly and systemic inflammation. Secondary HLH can be triggered by various aetiologies including infections, malignancies and autoimmune conditions. We highlight the complexity of HLH diagnosis and management by describing a case of an adolescent Salvadoran immigrant with HLH, newly diagnosed HIV, Streptococcal bacteraemia and disseminated histoplasmosis. The patient presented with neurological and ocular findings along with persistent fevers and cytopenia. He was diagnosed with HLH and treated with anakinra in addition to receiving treatment for HIV, Streptococcal bacteraemia and histoplasmosis. The patient's HLH resolved without corticosteroids or chemotherapy, which are considered the mainstays for HLH treatment. This case underscores the need for the evaluation and management of multiple infections and individualised management in patients presenting with HLH to achieve favourable outcomes.

Mpox (Monkeypox) Virus and Its Co-Infection with HIV, Sexually Transmitted Infections, or Bacterial Superinfections: Double Whammy or a New Prime Culprit?

Epidemiologic studies have established that mpox (formerly known as monkeypox) outbreaks worldwide in 2022-2023, due to Clade IIb mpox virus (MPXV), disproportionately affected gay, bisexual, and other men who have sex with men. More than 35% and 40% of the mpox cases suffer from co-infection with HIV and sexually transmitted infections (STIs) (e.g., Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, and herpes simplex virus), respectively. Bacterial superinfection can also occur. Co-infection of MPXV and other infectious agents may enhance disease severity, deteriorate outcomes, elongate the recovery process, and potentially contribute to the morbidity and mortality of the ensuing diseases. However, the interplays between MPXV and HIV, bacteria, other STI pathogens and host cells are poorly studied. There are many open questions regarding the impact of co-infections with HIV, STIs, or bacterial superinfections on the diagnosis and treatment of MPXV infections, including clinical and laboratory-confirmed mpox diagnosis, suboptimal treatment effectiveness, and induction of antiviral drug resistance. In this review article, we will discuss the progress and knowledge gaps in MPXV biology, antiviral therapy, pathogenesis of human MPXV and its co-infection with HIV, STIs, or bacterial superinfections, and the impact of the co-infections on the diagnosis and treatment of mpox disease. This review not only sheds light on the MPXV infection and co-infection of other etiologies but also calls for more research on MPXV life cycles and the molecular mechanisms of pathogenesis of co-infection of MPXV and other infectious agents, as well as research and development of a novel multiplex molecular testing panel for the detection of MPXV and other STI co-infections.

Pharmacokinetics and safety of coformulated bictegravir, emtricitabine, and tenofovir alafenamide in children aged 2 years and older with virologically suppressed HIV: a phase 2/3, open-label, single-arm study.

BACKGROUND: Coformulated bictegravir, emtricitabine, and tenofovir alafenamide is a single-tablet regimen and was efficacious and well tolerated in children and adolescents with HIV (aged 6 years to <18 years) in a 48-week phase 2/3 trial. In this study, we report data from children aged at least 2 years and weighing 14 kg to less than 25 kg. METHODS: We conducted this open-label, multicentre, multicohort, single-arm study in South Africa, Thailand, Uganda, and the USA. Participants were virologically suppressed children with HIV, aged at least 2 years, weighing 14 kg to less than 25 kg. Participants received bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) once daily, switching to bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) upon attaining a bodyweight of at least 25 kg. The study included pharmacokinetic evaluation at week 2 to confirm the dose of coformulated bictegravir, emtricitabine, and tenofovir alafenamide for this weight band by comparing with previous adult data. Primary outcomes were bictegravir area under the curve over the dosing interval (AUCtau) and concentration at the end of the dosing interval (Ctau) at week 2, and incidence of treatment-emergent adverse events and laboratory abnormalities until the end of week 24 in all participants who received at least one dose of bictegravir, emtricitabine, and tenofovir alafenamide. This study is registered with ClinicalTrials.gov, NCT02881320. FINDINGS: Overall, 22 participants were screened (from Nov 14, 2018, to Jan 11, 2020), completed treatment with bictegravir, emtricitabine, and tenofovir alafenamide (until week 48), and entered an extension phase. The geometric least squares mean (GLSM) ratio for AUCtau for bictegravir was 7·6% higher than adults (GLSM ratio 107·6%, 90% CI 96·7-119·7); Ctau was 34·6% lower than adults (65·4%, 49·1-87·2). Both parameters were within the target exposure range previously found in adults, children, or both". Grade 3-4 laboratory abnormalities occurred in four (18%) participants by the end week 24 and six (27%) by the end of week 48. Drug-related adverse events occurred in three participants (14%) by the end of week 24 and week 48; none were severe. No Grade 3-4 adverse events, serious adverse events, or adverse events leading to discontinuation occurred by the end of week 24 and week 48. INTERPRETATION: Data support the use of single-tablet coformulated bictegravir (30 mg), emtricitabine (120 mg), and tenofovir alafenamide (15 mg) for treatment of HIV in children aged at least 2 years and weighing 14 kg to less than 25 kg. FUNDING: Gilead Sciences.

Experiences of adolescents and youth with HIV testing and linkage to care through the Red Carpet Program (RCP) in Kenya.

Adolescents and youth living with HIV (AYLHIV) experience worse health outcomes compared to adults. We aimed to understand the experiences of AYLHIV in care in the youth-focused Red-Carpet program in Kenya to assess the quality of service provision and identify programmatic areas for optimization. We conducted focus group discussions among 39 AYLHIV (15-24 years) and structured analysis into four thematic areas. Within the HIV testing theme, participants cited fear of positive results, confidentiality and stigma concerns, and suggested engaging the community and youth in HIV testing opportunities. Within the HIV treatment adherence theme, participants cited forgetfulness, stigma, adverse side effects, lack of family support, and treatment illiteracy as barriers to adherence. Most participants reported positive experiences with healthcare providers and peer support. In terms of the HIV status disclosure theme, AYLHIV cited concerns about their future capacity to conceive children and start families and discussed challenges with understanding HIV health implications and sharing their status with friends and partners. Youth voices informing service implementation are essential in strengthening our capacity to optimize the support for AYLHIV within the community, at schools and healthcare facilities.

The Mental Health Effects and Experiences of Breastfeeding Decision-Making Among Postpartum Women Living with HIV.

Prior to January 2023, women living with HIV (WLWH) in the United States (US) were discouraged from breastfeeding due to the potential risk of mother-to-child HIV transmission through breastfeeding. Lack of breastfeeding decision-making and experience among WLWH may negatively affect maternal mental health. We implemented a quality improvement initiative to screen WLWH for postpartum depression (PPD), evaluate their attitudes toward breastfeeding, and assess their experience with breastfeeding decision-making. We collected quantitative data from WLWH using a voluntary, self-administered 6-item breastfeeding decision-making and experience survey (administered 1 month postpartum) and a 10-item Edinburgh Postnatal Depression Scale (EPDS, negative = 0-9; administered 1 and 4 months postpartum) tool. We conducted descriptive statistics and cross tabulation analysis. We analyzed 106 WLWH (93.4% non-Hispanic Black/African American; mean age 33.1 years; 82.1% HIV RNA < 200 copies/mL). One in five (19.1%) WLWH had a positive baseline EPDS screen, with the mean EPDS scores decreasing from 5.3 ± 5.4 (baseline) to 4.6 ± 4.8 (follow-up). Among 55 WLWH who provided baseline and follow-up EPDS scores, only 3/13 with a positive baseline EPDS screen had resolved depressive symptoms at follow-up. Over one-third (37.7%) of WLWH indicated feeling "sadness" when asked whether lack of breastfeeding negatively affected their feelings or emotions. Over half of WLWH (51.9%) were aware of the US breastfeeding recommendations, but the majority (60.4%) had never discussed breastfeeding options with a medical provider. Improved provider-patient discussions on infant feeding options among WLWH is needed to increase awareness of breastfeeding choices and promote informed, autonomous breastfeeding decision-making among WLWH.

Patient Perspectives on Telehealth for HIV and Mental Health Care at a Pediatric and Adolescent HIV Clinic in Washington, DC.

Despite the scale-up of telehealth for children and youth living with HIV during the COVID-19 pandemic, their experience and interest in continued telehealth use in the future is unknown. We conducted a quality improvement project to identify areas for improvement of telehealth delivery to children and youth living with HIV and evaluate youth's experiences when using telehealth for mental health services. Children and youth living with HIV (up to 24 years) seen at a specialty HIV program during 2020-2021 were surveyed regarding technology access, telehealth knowledge, barriers to telehealth use and interest in future telehealth use for HIV care. Youth (12-<24 years) who used telehealth for mental health services were surveyed regarding their experiences. Data were analyzed using descriptive statistics. Of the 170 patients in care, we surveyed 103 children and youth living with HIV (median age 17.6 years, 88.3% Black, 52.4% female, 77.7% perinatally infected), of whom 69.9% had prior telehealth use for their clinical visit. Most patients had access to a device with internet (99%) and were interested in future telehealth use for HIV care (87.4%). Reasons for not wanting to use telehealth included privacy concerns, distrust, discomfort with telehealth, preferring in-person visits, technology access issues and needing translation services. Most youth (81%) surveyed regarding telehealth for mental health services were satisfied and very likely to recommend it to others. Despite some reported barriers to telehealth, there is a high desirability for continued telehealth use among children and youth receiving HIV care.

Mechanistic Modeling of the Drug-Drug Interaction Between Efavirenz and Dolutegravir: Is This Interaction Clinically Relevant When Switching From Efavirenz to Dolutegravir During Pregnancy?

Following the 2021 World Health Organization's updated recommendations on the management of HIV infection, millions of people living with HIV are currently switched from efavirenz-based antiretroviral therapy to dolutegravir-based antiretroviral therapy. Pregnant individuals transitioning from efavirenz to dolutegravir might be at increased risk of insufficient viral suppression in the immediate postswitch period because both efavirenz- and pregnancy-related increases in hormone levels induce enzymes involved in dolutegravir metabolism, namely, cytochrome P450 3A4 and uridine 5'-diphospho-glucuronosyltransferase 1A1. This study aimed at developing physiologically based pharmacokinetic models to simulate the switch from efavirenz to dolutegravir in the late second and third trimester. To this end, the drug-drug interaction between efavirenz and the uridine 5'-diphospho-glucuronosyltransferase 1A1 substrates dolutegravir and raltegravir was first simulated in nonpregnant subjects. After successful validation, the physiologically based pharmacokinetic models were translated to pregnancy and dolutegravir pharmacokinetics following efavirenz discontinuation were predicted. Modeling results indicated that, at the end of the second trimester, both efavirenz concentrations and dolutegravir trough concentrations fell below respective pharmacokinetic target thresholds (defined as reported thresholds producing 90%-95% of the maximum effect) during the time interval from 9.75 to 11 days after dolutegravir initiation. At the end of the third trimester, this time interval spanned from 10.3 days to >4 weeks after dolutegravir initiation. These findings suggest that dolutegravir exposure in the immediate post-efavirenz switch period during pregnancy may be suboptimal, leading to HIV viremia and, potentially, resistance. The clinical implications of these findings remain to be substantiated by future studies.

Breastfeeding Among People With Human Immunodeficiency Virus in North America: A Multisite Study.

BACKGROUND: In North American countries, national guidelines have strongly recommended formula over breastmilk for people with human immunodeficiency virus (HIV) because of concern for HIV transmission. However, data from resource-limited settings suggest the risk is <1% among virally suppressed people. Information regarding breastfeeding experience in high-resource settings is lacking. METHODS: A retrospective multisite study was performed for individuals with HIV who breastfed during 2014-2022 in the United States (8 sites) and Canada (3 sites). Descriptive statistics were used for data analysis. RESULTS: Among the 72 cases reported, most had been diagnosed with HIV and were on antiretroviral therapy prior to the index pregnancy and had undetectable viral loads at delivery. Most commonly reported reasons for choosing to breastfeed were health benefits, community expectations, and parent-child bonding. Median duration of breastfeeding was 24 weeks (range, 1 day to 72 weeks). Regimens for infant prophylaxis and protocols for testing of infants and birthing parents varied widely among institutions. No neonatal transmissions occurred among the 94% of infants for whom results were available ≥6 weeks after weaning. CONCLUSIONS: This study describes the largest cohort to date of people with HIV who breastfed in North America. Findings demonstrate high variability among institutions in policies, infant prophylaxis, and infant and parental testing practices. The study describes challenges in weighing the potential risks of transmission with personal and community factors. Finally, this study highlights the relatively small numbers of patients with HIV who chose to breastfeed at any 1 location, and the need for further multisite studies to identify best care practices.

Advancing the prevention and treatment of HIV in children: priorities for research and development.

Safe and effective paediatric formulations of the most promising antiretroviral drugs are crucial to advance the treatment and prevention of HIV in neonates, infants, children, and adolescents. The WHO Paediatric Drug Optimization for HIV (PADO-HIV) group brings together stakeholders and experts every 2-3 years to identify priority products and define research gaps in the development of new HIV drugs and formulations for children in low-income and middle-income countries. PADO-HIV 5 met from Sept 27 to Oct 15, 2021. The group evaluated HIV agents from known and novel drug classes, oral and parenteral long-acting formulations, and developments in broadly neutralising antibodies, and included focused sessions on neonates and new delivery technologies. A list of medium-term and long-term priorities was generated, and research questions were defined. This forward-looking analysis is intended to provide guidance to funders, drug developers, and researchers, and to accelerate access for children to the best HIV drugs and formulations.

Short Communication:Outcomes of Dual Versus Triple Antiretroviral Drug Regimens Among Virally Suppressed Adults in the DC Cohort.

This study explored virological outcomes of two-drug (2DRs) and three-drug (3DRs) antiretroviral regimens in adults with HIV in the DC Cohort. We analyzed 310 treatment-experienced adults with sustained HIV RNA ≤50 copies/mL at baseline, 53 of whom switched to 2DRs and 257 continued 3DRs. Adults on 2DRs and 3DRs had similar demographics (median age 53.3 years, 76.8% cisgender male, 76.1% Black). Adults on 2DRs had more participants with ≥2 comorbidities (62.3% vs. 42.8%, p = .019), had a longer time since HIV diagnosis (median years 20.4 vs. 13.2, p = .017), and received the regimen of interest for a shorter duration (median years 1.3 vs. 3.3, p < .001) compared with adults on 3DRs. Adults receiving 2DRs had a higher, although nonsignificant, risk for virological failure (two consecutive HIV RNA ≥50 copies/mL) at 24 months follow-up than adults on 3DRs (6.7% vs. 1.7%, respectively; p = .10). Future analysis of the effectiveness of 2DRs is needed.