Amphiregulin Aggravates Glomerulonephritis via Recruitment and Activation of Myeloid Cells

BACKGROUND

Recent studies have identified the EGF receptor (EGFR) ligand amphiregulin (AREG) as an important mediator of inflammatory diseases. Both pro- and anti-inflammatory functions have been described, but the role of AREG in GN remains unknown.

METHODS

The nephrotoxic nephritis model of GN was studied in AREG^-/- mice after bone marrow transplantation, and in mice with myeloid cell-specific EGFR deficiency. Therapeutic utility of AREG neutralization was assessed. Furthermore, AREG's effects on renal cells and monocytes/macrophages (M/M) were analyzed. Finally, we evaluated AREG expression in human renal biopsies.

RESULTS

Renal AREG mRNA was strongly upregulated in murine GN. Renal resident cells were the most functionally relevant source of AREG. Importantly, the observation that knockout mice showed significant amelioration of disease indicates that AREG is pathogenic in GN. AREG enhanced myeloid cell responses via inducing chemokine and colony stimulating factor 2 (CSF2) expression in kidney resident cells. Furthermore, AREG directly skewed M/M to a proinflammatory M1 phenotype and protected them from apoptosis. Consequently, anti-AREG antibody treatment dose-dependently ameliorated GN. Notably, selective abrogation of EGFR signaling in myeloid cells was sufficient to protect against nephritis. Finally, strong upregulation of AREG expression was also detected in kidneys of patients with two forms of crescentic GN.

CONCLUSIONS

AREG is a proinflammatory mediator of GN via (1) enhancing renal pathogenic myeloid cell infiltration and (2) direct effects on M/M polarization, proliferation, and cytokine secretion. The AREG/EGFR axis is a potential therapeutic target for acute GN.

FRI0089 COMPARATIVE EFFICACY (ACR 20) OF TOCILIZUMAB TO OTHER TARGETED IMMUNE MODULATORS (TIM) FOR RHEUMATOID ARTHRITIS: A NETWORK META-ANALYSIS (NMA)

Background:

Clinical trial and real-world evidence have both firmly established efficacy and safety of intravenous (IV) and subcutaneous (SC) tocilizumab, both as monotherapy or in combination with a conventional disease modifying antirheumatic drug (cDMARD). However, tocilizumab’s relative efficacy to the new Janus kinase (JAK) inhibitor class of therapies is less certain, given the lack of head-to-head trials.

Objectives:

To evaluate the relative efficacy of: 1) combination tocilizumab plus cDMARD to other TIMs plus a cDMARD in TIM-naïve or mixed (<20% TIM-experienced) adults with moderate to severe RA; 2) tocilizumab monotherapy to other TIM monotherapies in TIM-naïve or mixed adults with moderate to severe RA. Efficacy was defined as achievement of an ACR20 response or better at 24 weeks.

Methods:

Randomized controlled trials (RCTs) were selected from a recent systematic literature review conducted by the Institute for Clinical and Economic Review (ICER), as well as from a trial for upadacitinib (SELECT-COMPARE,NCT02629159), which was not included in the ICER 2017 report. Treatments included JAK inhibitors (upadacitinib, baricitinib, and tofacitinib), tumor necrosis factor alpha inhibitors (TNFi; adalimumab, certolizumab pegol, etanercept, golimumab, and infliximab), and other non-TNFis (rituximab, sarilumab, tocilizumab, and abatacept). A Bayesian NMA was performed in OpenBUGS and R to evaluate comparative efficacy using a random effects model for combination therapy and fixed effects model for monotherapy. Model selection was based on deviance information criterion. Forest plots of relative risks (RR) are presented.

Results:

In combination therapy analysis, a total of 35 studies were included with a pooled study population of 17,508 patients. Study populations were predominantly female (mean 79%, range 39-95%), and had a baseline mean age of 52 years (range 47-58), mean disease duration of 8 years (range 2-12), and mean DAS28 score of 6 (range 5-7). When compared to cDMARD, all TIMs were 1.69 to 2.22 times more likely to achieve an ACR20 response or better at 24 Weeks (statistically significant) (Figure 1). In pair-wise comparison, tocilizumab IV and SC did not differ from all other TIMs, including JAK inhibitors (no statistically significant difference).

In monotherapy analysis, a total of 5 studies were included with a pooled study population of 1,189 patients. Study populations were predominantly female (mean 82%, range 75-90%), had a baseline mean age of 53 years (range 51-54), mean disease duration of 6 years (range 2-9), and mean DAS28 score of 6 (range 5-7). When compared to cDMARD, all TIMs were 1.65 to 1.84 times more likely to achieve ACR20 response or better (statistically significant) (Figure 2). In pair-wise comparison, tocilizumab IV was associated with a greater likelihood of achieving an ACR20 response or better compared to adalimumab (RR=1.10, 95% credible interval (Crl) = 1.03,1.29).

Conclusion:

Results of this NMA demonstrate similar efficacy (ACR20 at week 24) between tocilizumab (IV and SC) and other TIMs, including new JAK inhibitors, when used in combination with a cDMARD among TIM-naïve/mixed patient populations. Tocilizumab IV monotherapy had more favorable efficacy than adalimumab monotherapy. Patients unable to tolerate cDMARDs may experience additional value from tocilizumab compared to adalimumab.

Acknowledgments:

This study was sponsored and funded by Genentech, Inc.

Disclosure of Interests:

Joseph Dang Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Jennifer Uyei: None declared, Yilin Jiang: None declared, Rajpal Singh: None declared, Pinar Bilir: None declared, Andreas Karabis: None declared, Julie Munakata: None declared, Margaret Michalska Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Jennie H. Best Shareholder of: Genentech, Inc., Employee of: Genentech, Inc.

SAT0125 ASSOCIATION BETWEEN CHANGE IN HEALTH ASSESSMENT QUESTIONNAIRE DISABILITY INDEX AND TREATMENT RESPONSE IN PATIENTS WITH RHEUMATOID ARTHRITIS IN TOCILIZUMAB CLINICAL TRIALS

Background:

The efficacy and safety of intravenous (IV) and subcutaneous (SC) tocilizumab (TCZ) in combination with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and as monotherapy in patients with rheumatoid arthritis (RA) has been demonstrated in large clinical trials and real-world data studies. The Health Assessment Questionnaire Disability Index (HAQ-DI) is commonly used to assess physical function in patients with RA. While HAQ-DI outcomes at Week 24 in TCZ clinical trials have been reported, outcomes at Week 12 and results stratified by treatment response categories at Weeks 12 and 24 have not been previously described.

Objectives:

To report the association between change in HAQ-DI from baseline to Weeks 12 and 24 and Disease Activity Score in 28 joints (DAS28) response categories in patients who received TCZ or comparators in TCZ clinical trials.

Methods:

Data from patients with active RA who received TCZ or a comparator from 6 Phase III or IV TCZ-IV studies (OPTION [NCT00106548], RADIATE [NCT00106522], TOWARD [NCT00106574] LITHE [NCT00109408], ACT-RAY [NCT00810199] and ADACTA [NCT01119859]) and 1 Phase III TCZ-SC study (BREVACTA [NCT01232569]) were analyzed. Mean change in HAQ-DI score at Weeks 12 and 24 was assessed in patients stratified by DAS28 disease activity level (DAS28 < 2.6 [remission], DAS28 ≥ 2.6 to ≤ 3.2 [low disease activity; LDA], DAS28 > 3.2 to ≤ 5.1 [moderate disease activity; MDA], DAS28 > 5.1 [high disease activity; HDA] at Weeks 12 and 24. The adjusted least squares mean (LSM) change from baseline was estimated using a mixed model with repeated measures, including region (North America vs non-North America), RA duration (> 2 years vs ≤ 2 years), baseline HAQ-DI and DAS28, treatment, visit, visit by treatment and visit by baseline HAQ-DI.

Results:

Data from 5051 patients were included. Across all studies, the mean duration of RA ranged from 6.3 to 12.6 years. At baseline, patients had severe RA with a mean DAS28 ≥ 6.3; baseline HAQ-DI was ≥ 1.5. At Week 12, patients who achieved remission or LDA had greater improvements in HAQ-DI than those in MDA or HDA (Figure 1). Results were similar at Week 24 (Figure 2). Among patients who received TCZ and achieved remission or LDA, mean improvement in HAQ-DI was ≥ 0.65 and ≥ 0.44, respectively, at Week 12 (Figure 1) and ≥ 0.48 and ≥ 0.43 at Week 24 (Figure 2). Mean changes in HAQ-DI were similar between patients who received TCZ-IV in combination with MTX or as monotherapy (ACT-RAY) and in those who received TCZ-IV or ADA as monotherapy (ADACTA).

Conclusion:

Patients with long-standing, severe RA who received IV or SC TCZ as monotherapy or in combination with csDMARDs had improvement in physical function and disease activity at Week 12 that was maintained at Week 24. Overall, across all the trials, response to treatment was associated with improvement in physical function.

Acknowledgments :

This study was sponsored by Genentech, Inc. Support for third-party writing assistance, furnished by Health Interactions, Inc, was provided by Genentech, Inc.

Disclosure of Interests: :

Sebastian Unizony Grant/research support from: Genentech, Inc., Joseph Dang Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Jian Han Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Margaret Michalska Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Jennie H. Best Shareholder of: Genentech, Inc., Employee of: Genentech, Inc.

AB0275 COMPARATIVE EFFICACY (DAS 28) OF TOCILIZUMAB AND OTHER TARGETED IMMUNE MODULATORS (TIMS) FOR RHEUMATOID ARTHRITIS: A NETWORK META-ANALYSIS (NMA)

Background:

With a ‘treat to target’ approach in RA, guidelines recommend tailored monitoring of disease activity using validated composite instruments, such as the disease activity score (DAS) 28. While response assessment at 24 weeks is the standard in clinical trials, assessment as early as 12 weeks is recommended. There is limited evidence assessing the relative efficacy of TIMs following a ‘treat to target’ strategy.

Objectives:

To evaluate the relative efficacy of intravenous (IV) and subcutaneous (SC) tocilizumab plus a conventional disease modifying antirheumatic drug (cDMARD) to other TIMs plus a cDMARD in TIM-naïve or mixed (<20% TIM-experienced) adults with moderate to severe RA. Efficacy was defined as achieving remission according to a DAS28 score <2.6 at 12 and 24 weeks.

Methods:

Randomized controlled trials (RCTs) were selected from a recent systematic literature review conducted by the Institute for Clinical and Economic Review (ICER), as well as from trials for upadacitinib (SELECT-NEXT, SELECT-COMPARE), which were not included in the ICER 2017 report. RCTs that compared TIMs to each other or placebo were included. Treatments included Janus kinase (JAK) inhibitors (upadacitinib, baricitinib, and tofacitinib), tumor necrosis factor alpha inhibitors (TNFi; adalimumab, certolizumab pegol, golimumab, and infliximab), and other non-TNFis (rituximab, sarilumab, tocilizumab, and abatacept). A Bayesian NMA was performed in OpenBUGS and R using a fixed effects model. Model selection was based on deviance information criterion. Forest plots of odds ratios (OR) are presented.

Results:

In the 12-week analysis, 15 trials were included with a pooled study population of 9,154 patients. Populations were similar across trials and predominantly female (mean 78%, range 39-87%), with a baseline mean age of 52 years (range 47-56), mean disease duration of 8 years (range 2-11), and mean DAS28 score of 6 (range 5-7). In the 12-week analysis, compared to cDMARD, all TIMs were more likely to achieve remission (statistically significant), but tocilizumab IV showed a substantially greater magnitude of effect (OR=19.3, 95% Crl=10.99, 37.22) which was consistent with raw trial results (Figure 1). In pair-wise comparison, tocilizumab IV was associated with a greater likelihood of achieving remission compared to abatacept IV (OR=7.47, Crl=2.53, 20.89), abatacept SC (OR=4.29, Crl=1.96, 9.94), baricitinib (OR=3.39, Crl=1.74, 7.09), adalimumab (OR=5.10, Crl=2.68,10.42), tofacitinib (OR=5.44, Crl=1.26, 20.57), upadacitinib 15mg (OR=3.23, Crl=1.72, 6.54), and upadacitinib 30mg (OR=4.05, Crl=1.97, 8.85).

In the 24-week analysis, 21 trials were included in the analysis with a pooled study population of 12,180 patients. Patient characteristics were the same as the 12 week analysis. Compared to cDMARD, all TIMs were more likely to achieve remission (statistically significant), with tocilizumab IV and SC showing a greater magnitude of effect (OR=12.08, Crl=8.09-18.30 and OR=11.98, Crl=5.17-35.86, respectively) (Figure 2). In pair-wise comparison, tocilizumab IV and SC were associated with a greater likelihood of achieving remission compared to abatacept IV, adalimumab, baricitinib, infliximab, upadacitinib 15 mg, and sarilumab.

Conclusion:

Results of this NMA demonstrate that tocilizumab is associated with a greater likelihood of remission (DAS28 <2.6) at 12 and 24 weeks compared to most other TIMs including new JAK inhibitors, when used in combination with a cDMARD among TIM-naïve/mixed patient populations.

Acknowledgments:

This study was sponsored and funded by Genentech, Inc.

Disclosure of Interests:

Jennie H. Best Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Jennifer Uyei: None declared, Joseph Dang Shareholder of: Genentech, Inc., Employee of: Genentech, Inc., Yilin Jiang: None declared, Rajpal Singh: None declared, Pinar Bilir: None declared, Andreas Karabis: None declared, Julie Munakata: None declared, William Reiss Shareholder of: Genentech, Inc., Employee of: Genentech, Inc.

Clinical efficacy of hydroxychloroquine in patients with covid-19 pneumonia who require oxygen: observational comparative study using routine care data

OBJECTIVE

To assess the effectiveness of hydroxychloroquine in patients admitted to hospital with coronavirus disease 2019 (covid-19) pneumonia who require oxygen.

DESIGN

Comparative observational study using data collected from routine care.

SETTING

Four French tertiary care centres providing care to patients with covid-19 pneumonia between 12 March and 31 March 2020.

PARTICIPANTS

181 patients aged 18-80 years with documented severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia who required oxygen but not intensive care.

INTERVENTIONS

Hydroxychloroquine at a dose of 600 mg/day within 48 hours of admission to hospital (treatment group) versus standard care without hydroxychloroquine (control group).

MAIN OUTCOME MEASURES

The primary outcome was survival without transfer to the intensive care unit at day 21. Secondary outcomes were overall survival, survival without acute respiratory distress syndrome, weaning from oxygen, and discharge from hospital to home or rehabilitation (all at day 21). Analyses were adjusted for confounding factors by inverse probability of treatment weighting.

RESULTS

In the main analysis, 84 patients who received hydroxychloroquine within 48 hours of admission to hospital (treatment group) were compared with 89 patients who did not receive hydroxychloroquine (control group). Eight additional patients received hydroxychloroquine more than 48 hours after admission. In the weighted analyses, the survival rate without transfer to the intensive care unit at day 21 was 76% in the treatment group and 75% in the control group (weighted hazard ratio 0.9, 95% confidence interval 0.4 to 2.1). Overall survival at day 21 was 89% in the treatment group and 91% in the control group (1.2, 0.4 to 3.3). Survival without acute respiratory distress syndrome at day 21 was 69% in the treatment group compared with 74% in the control group (1.3, 0.7 to 2.6). At day 21, 82% of patients in the treatment group had been weaned from oxygen compared with 76% in the control group (weighted risk ratio 1.1, 95% confidence interval 0.9 to 1.3). Eight patients in the treatment group (10%) experienced electrocardiographic modifications that required discontinuation of treatment.

CONCLUSIONS

Hydroxychloroquine has received worldwide attention as a potential treatment for covid-19 because of positive results from small studies. However, the results of this study do not support its use in patients admitted to hospital with covid-19 who require oxygen.

Bedside prediction of intradialytic hemodynamic instability in critically ill patients: the SOCRATE study

BACKGROUND

Despite improvements in intermittent hemodialysis management, intradialytic hemodynamic instability (IHI) remains a common issue that could account for increased mortality and delayed renal recovery. However, predictive factors of IHI remain poorly explored. The objective of this study was to evaluate the relationship between baseline macrohemodynamic, tissue hypoperfusion parameters and IHI occurrence.

METHODS

Prospective observational study conducted in a 18-bed medical ICU of a tertiary teaching hospital. Cardiovascular SOFA score, index capillary refill time (CRT) and lactate level were measured just before (T0) consecutive intermittent hemodialysis sessions performed for AKI. The occurrence of IHI requiring a therapeutic intervention was recorded.

RESULTS

Two hundred eleven sessions, corresponding to 72 (34%) first sessions and 139 (66%) later sessions, were included. As IHI mostly occurred during first sessions (43% vs 12%, P < 0.0001), following analyses were performed on the 72 first sessions. At T0, cardiovascular SOFA score ≥1 (87% vs 51%, P = 0.0021) was more frequent before IHI sessions, as well as index CRT ≥ 3 s (55% vs 15%, P = 0.0004), and hyperlactatemia > 2 mmol/L (68% vs 29%, P = 0.0018). Moreover, the occurrence of IHI increased with the number of macrohemodynamic and tissue perfusion impaired parameters, named SOCRATE score (cardiovascular SOFA, index CRT and lactATE): 10% (95% CI [3%, 30%]), 33% (95% CI [15%, 58%]), 55% (95% CI [35%, 73%]) and 80% (95% CI [55%, 93%]) for 0, 1, 2 and 3 parameters, respectively (AUC = 0.79 [0.69-0.89], P < 0.0001). These results were confirmed by analyzing the 139 later sessions included in the study.

CONCLUSIONS

The SOCRATE score based on 3 easy-to-use bedside parameters correlates with the risk of IHI. By improving risk stratification of IHI, this score could help clinicians to manage intermittent hemodialysis initiation in critically ill AKI patients.

In-hospital management of acute complicated urinary tract infections

Upper tract urinary tract infections that require hospitalization have been the focus of national recommendations in 2018 by the French society of infectious diseases (Spilf). We here propose to discuss several complex-challenging situations: severe infection with sepsis, pyelonephritis in the pregnant woman, management of infections involving multiresistant bacteria and infection in polycystic kidney disease.

Renal Infarction and Its Consequences for Renal Function in Patients With Cardiac Amyloidosis

OBJECTIVE

To describe the prevalence of and risk factors for renal infarction (RI) in patients with cardiac amyloidosis.

PATIENTS AND METHODS

We evaluated 87 patients with cardiac amyloidosis who underwent renal technetium-99m-labeled dimercaptosuccinic acid scintigraphy in the Amyloidosis Referral Center of Henri-Mondor Hospital from October 1, 2015, through February 28, 2018.

RESULTS

Three groups of patients were identified according to the underlying amyloidosis disorder: AL amyloidosis in 24 patients, mutated-transthyretin amyloidosis in 24 patients, and wild-type transthyretin amyloidosis in 39 patients. Patients with wild-type transthyretin amyloidosis were older (P<.001), more likely to be men (P=.02), to have arrhythmic heart diseases (P<.001), and to be receiving anticoagulation treatment (P<.001). Patients with AL amyloidosis had significantly higher N-terminal pro-B-type natriuretic peptide levels (P=.02) and were more likely to have nephrotic syndrome (P<.001). Renal infarction was detected in 18 patients (20.7%), at similar frequencies in the various groups. Baseline urinary protein to creatinine ratio was the only parameter for which a significant difference (P=.03) was found between patients with and without RI diagnoses. The likelihood of RI diagnosis was 47.1% (8 of 17) in the presence of AKI and 14.5% (10 of 69) in its absence (P=.003). Overall, heart transplant-censored patient survival did not differ significantly between patients with and without RI (P=.64), but death- and heart transplant-censored renal survival was significantly lower in patients with RI (P<.001).

CONCLUSION

Our study suggests that prevalence of RI in patients with cardiac amyloidosis is higher than previously thought, regardless of the underlying amyloidosis disorder. Acute kidney injury in a patient with cardiac amyloidosis should alert clinicians to the possibility of RI.

Respiratory signal prediction based on adaptive boosting and multi-layer perceptron neural network

To improve the prediction accuracy of respiratory signals using adaptive boosting and multi-layer perceptron neural network (ADMLP-NN) for gated treatment of moving target in radiation therapy. The respiratory signals acquired using a real-time position management (RPM) device from 138 previous 4DCT scans were retrospectively used in this study. The ADMLP-NN was composed of several artificial neural networks (ANNs) which were used as weaker predictors to compose a stronger predictor. The respiratory signal was initially smoothed using a Savitzky-Golay finite impulse response smoothing filter (S-G filter). Then, several similar multi-layer perceptron neural networks (MLP-NNs) were configured to estimate future respiratory signal position from its previous positions. Finally, an adaptive boosting (Adaboost) decision algorithm was used to set weights for each MLP-NN based on the sample prediction error of each MLP-NN. Two prediction methods, MLP-NN and ADMLP-NN (MLP-NN plus adaptive boosting), were evaluated by calculating correlation coefficient and root-mean-square-error between true and predicted signals. For predicting 500 ms ahead of prediction, average correlation coefficients were improved from 0.83 (MLP-NN method) to 0.89 (ADMLP-NN method). The average of root-mean-square-error (relative unit) for 500 ms ahead of prediction using ADMLP-NN were reduced by 27.9%, compared to those using MLP-NN. The preliminary results demonstrate that the ADMLP-NN respiratory prediction method is more accurate than the MLP-NN method and can improve the respiration prediction accuracy.

AMKL chimeric transcription factors are potent inducers of leukemia

Acute megakaryoblastic leukemia in patients without Down syndrome is a rare malignancy with a poor prognosis. RNA sequencing of fourteen pediatric cases previously identified novel fusion transcripts that are predicted to be pathological including CBFA2T3-GLIS2, GATA2-HOXA9, MN1-FLI and NIPBL-HOXB9. In contrast to CBFA2T3-GLIS2, which is insufficient to induce leukemia, we demonstrate that the introduction of GATA2-HOXA9, MN1-FLI1 or NIPBL-HOXB9 into murine bone marrow induces overt disease in syngeneic transplant models. With the exception of MN1, full penetrance was not achieved through the introduction of fusion partner genes alone, suggesting that the chimeric transcripts possess a unique gain-of-function phenotype. Leukemias were found to exhibit elements of the megakaryocyte erythroid progenitor gene expression program, as well as unique leukemia-specific signatures that contribute to transformation. Comprehensive genomic analyses of resultant murine tumors revealed few cooperating mutations confirming the strength of the fusion genes and their role as pathological drivers. These models are critical for both the understanding of the biology of disease as well as providing a tool for the identification of effective therapeutic agents in preclinical studies.

A 54-Year-Old Man With Lingual Granuloma and Multiple Pulmonary Excavated Nodules

A 54-year-old French man was admitted for evaluation of a chronic nodular lesion of the tongue and mandibular lymphadenopathy. He reported active tobacco and cannabis smoking as well as excessive alcohol use. He also reported frequent use of cocaine for several months and a past addiction to IV heroin. He had traveled abroad as a journalist and lived for several months in Columbia and Venezuela 12 years ago. His medical history included chronic hepatitis C infection successfully treated with interferon and ribavirin 6 years ago and high BP.

Single-nucleotide polymorphisms in dopamine receptor D1 are associated with heroin dependence but not impulsive behavior

Previous studies suggested that dopamine receptors may be associated with drug dependence and impulsive behavior. In this study, we examined whether dopamine receptor D1 (DRD1) is associated with heroin dependence and the impulsive behavior in patients with heroin dependence. The participants included 367 patients with heroin dependence and 372 healthy controls from a Chinese Han population. We examined the potential association between heroin dependence and 8 single-nucleotide polymorphisms (rs686, rs4867798, rs1799914, rs4532, rs5326, rs265981, rs10078714, rs10078866) of DRD1, and the associations between single single-nucleotide polymorphism, haplotypes, and impulsive behavior. Compared with the healthy controls, heroin dependence patients showed a significantly lower frequency of GG homozygotes of rs5326 (P = 0.027), significantly lower frequency of the G allele of rs5326 (P = 0.007, odds ratio = 0.718, 95% confidence interval = 0.565-0.913), and higher frequency of the rs265981 G allele (P = 0.0002, odds ratio = 1.711, 95% confidence interval = 1.281-2.287). Furthermore, strong linkage disequilibrium was observed in 2 blocks (D' > 0.9). However, no association was observed between haplotypes and heroin dependence in the 2 blocks. This genetic behavior correlation study showed that the 2 single-nucleotide polymorphisms, rs5326 and rs265981, were not associated with the impulsive behavior in patients with heroin dependence. These findings indicate that DRD1 gene polymorphisms are related to heroin dependence in a Chinese Han population and may be informative for future genetic or biological studies on heroin dependence.