177Lu-PSMA-617 versus docetaxel in chemotherapy-naïve metastatic castration-resistant prostate cancer: a randomized, controlled, phase 2 non-inferiority trial

[177Lu]Lu-PSMA-617 as first-line systemic therapy in patients with metastatic castration-resistant prostate cancer: a real-world study

PURPOSE

The use of [177Lu]Lu-PSMA-617 radioligand therapy has become increasingly recognized as a viable therapeutic approach for patients in the advanced stages of metastatic castration-resistant prostate cancer (mCRPC). However, there is limited data regarding its effectiveness and safety in earlier lines. This study aims to present our institution's experience with [177Lu]Lu-PSMA-617 as a first-line systemic therapy for mCRPC.

METHODS

We collected and analyzed data from consecutive mCRPC patients who underwent first-line treatment with [177Lu]Lu-PSMA-617 at our center from 2015 to 2023. The various outcome measures included best prostate-specific antigen-response rate (PSA-RR) (proportion of patients achieving a ≥ 50% decline in PSA); objective radiographic response rate (ORR) (proportion of patients achieving complete or partial radiographic responses); radiographic progression-free survival (rPFS) (measured from treatment initiation until radiographic progression or death from any cause); overall survival (OS) (measured from treatment initiation until death from any cause); and adverse events.

RESULTS

Forty treatment-naïve mCRPC patients with PSMA-positive disease on [68Ga]Ga-PSMA-11 PET/CT were included (median age: 68.5 years, range: 45-78; median PSA: 41 ng/mL, range: 1-3028). These patients received a median cumulative activity of 22.2 GBq (range: 5.55-44.4) [177Lu]Lu-PSMA-617 over 1-6 cycles at 8-12 week intervals. A ≥ 50% decline in PSA was observed in 25/40 (62.5%) patients (best PSA-RR). Radiographic responses were evaluated for thirty-eight patients, with thirteen showing partial responses (ORR 34.2%). Over a median follow-up of 36 months, the median rPFS was 12 months (95% confidence interval, CI: 9-15), and the median OS was 17 months (95% CI: 12-22). Treatment-emergent grade ≥ 3 anemia, leucopenia, and thrombocytopenia were noted in 4/40 (10%), 1/40 (2.5%), and 3/40 (7.5%) patients, respectively.

CONCLUSION

The findings suggest that [177Lu]Lu-PSMA-617 is a safe and effective option as a first-line treatment in mCRPC. Further trials are needed to definitively establish its role as an upfront treatment modality in this setting.

Highlighting recent progress in the treatment of men with advanced prostate cancer

PURPOSE OF REVIEW

This review is designed to highlight recent research efforts to optimize treatment strategies in men with advanced prostate cancer.

RECENT FINDINGS

Recent research analyses have suggested an overall survival advantage to treating some men with newly identified metastatic prostate cancer with a "triplet" of androgen deprivation therapy, docetaxel, and an androgen receptor axis-targeted agent (ARAT), but further work remains to refine which men need this aggressive of a treatment approach. Randomized trials have led to the approval of poly(ADP-ribose) polymerase inhibitor/ARAT agent combinations for some men with metastatic castration resistant prostate cancer, but the applicability of this approach to the growing number of men receiving combinations of systemic therapy in the castration-sensitive setting is unclear. Trials to refine use of prostate-specific membrane antigen (PSMA)-directed radiopharmaceuticals are ongoing, while novel treatment approaches targeting mechanisms driving advanced prostate cancer continue to be explored.

SUMMARY

Ongoing research focuses on refining the best combination and sequence of treatments for men with advanced prostate cancer. Future questions remain about use of existing therapies, and novel treatment approaches need to be developed.

Advancements in PSMA ligand radiolabeling for diagnosis and treatment of prostate cancer: a systematic review

Prostate cancer(PCa), a leading global health concern, profoundly impacts millions of men worldwide. Progressing through two stages, it initially develops within the prostate and subsequently extends to vital organs such as lymph nodes, bones, lungs, and the liver. In the early phases, castration therapy is often employed to mitigate androgen effects. However, when prostate cancer becomes resistant to this treatment, alternative strategies become imperative. As diagnostic and treatment methodologies for prostate cancer continually advance, radioligand therapy (RLT) has emerged as a promising avenue, yielding noteworthy outcomes. The fundamental principle of RLT involves delivering radionuclide drugs to cancerous lesions through specific carriers or technologies. Subsequently, these radionuclide drugs release radioactive energy, facilitating the destruction of cancer cell tissues. At present, the positron emission tomography (PET) targeting PSMA has been widely developed for the use of diagnosis and staging of PCa. Notably, FDA-approved prostate-specific membrane antigen (PSMA) targeting agents, such as 68Ga-PSMA-11 and 177Lu-PSMA-617, represent significant milestones in enhancing diagnostic precision and therapeutic efficacy. This review emphasizes the current research status and outcomes of various radionuclide-labeled PSMA ligands. The objective is to provide valuable insights for the continued advancement of diagnostic and therapeutic approaches in the realm of prostate cancer.

Promising Therapeutic Activity of 177 Lu-PSMA-617 in Synchronous High-Volume Metastatic Hormone-Sensitive Prostate Cancer : A Pilot Experience

PURPOSE

177 Lu-PSMA-617 has been shown to improve survival outcomes in patients with end-stage metastatic castration-resistant prostate cancer. However, data in earlier lines remain limited. In this study, we intended to evaluate the efficacy and safety of 177 Lu-PSMA-617 in patients with synchronous high-volume metastatic hormone-sensitive prostate cancer (mHSPC).

PATIENTS AND METHODS

Hormone-sensitive prostate cancer patients with synchronous high-volume metastases (defined as ≥4 skeletal metastases with ≥1 extra-axial site or any visceral metastasis) showing high PSMA expression on 68 Ga-PSMA-11 PET/CT and ineligible/unwilling for conventional chemohormonal treatment options were selected. Approximately, ~5.55-7.4 GBq of 177 Lu-PSMA-617 was administered intravenously at 8-12 weeks intervals, up to 6 cycles. All patients underwent concomitant androgen deprivation therapy/orchiectomy. The outcome measures included the proportion of patients achieving an undetectable serum prostate-specific antigen (PSA) (ie, ≤0.2 ng/mL) at any time point after therapy, best PSA response rate, objective radiographic response rate, radiographic progression-free survival, overall survival, and adverse events.

RESULTS

Ten patients with high-volume mHSPC received a median cumulative activity of 32.4 GBq (range, 7.4-44.4) of 177 Lu-PSMA-617 over 1-6 cycles. Five patients (50%) achieved an undetectable PSA with 9 patients (90%) showing a ≥50% decline in PSA from baseline. Nine patients underwent radiological follow-up, of which 7 (77.8%) had an objective response. The median radiographic progression-free survival was 24 months (95% confidence interval, 18-30), whereas the median overall survival was not reached. None of the patients had any grade 3/4 adverse event.

CONCLUSIONS

177 Lu-PSMA-617 seems to be a promising efficacious and safe treatment option for patients with synchronous high-volume mHSPC.

Estimation of absorbed dose to salivary glands in mCRPC patients undergoing 177 Lu- PSMA-617 radioligand therapy using quantitative SPECT-CT at single time point: a single-center feasibility study

OBJECTIVE

177 Lu-PSMA-617-radioligand therapy (RLT) has shown promising therapeutic role in patients with metastatic castration-resistant prostate cancer. However, off-target action in salivary glands often presents with xerostomia. Personalized dosimetry can help in optimizing the treatment, however, has so far been tedious due to multiple time-point imaging. In this prospective study, we intended to estimate the absorbed dose delivered to the salivary glands in patients undergoing 177 Lu-PSMA-617-RLT using quantitative SPECT/CT at a single time point.

METHODS

Patients undergoing 177 Lu-PSMA-617 RLT were included in this prospective study. Post-therapy whole-body images and regional quantitative single time-point SPECT/CT were acquired at 24 h with high-energy collimator. The data was processed and analyzed using Q.Metrix software. A scaling factor, that is, the time-integrated activity conversion factor was applied for the image acquired at 24 h. Absorbed doses were computed using MIRD scheme and OLINDA software.

RESULTS

A total of 21 patients (mean age: 66 ± 9 years) were included. The value of mean absorbed dose for the parotid glands was 1.90 ± 1.31Gy (range: 0.26-6.23) and that for the submandibular glands was 1.37 ± 0.94Gy (range: 0.16-3.65). The mean absorbed doses per administered activity for the parotid and submandibular glands were 0.26 ± 0.18 Gy/GBq and 0.19 ± 0.12 Gy/GBq, respectively. The absorbed doses were estimated for one cycle of therapy and were well within acceptable limits. None of the patients experienced dryness of mouth.

CONCLUSION

Single time-point dosimetry with quantitative SPECT/CT is feasible and can be standardized to estimate the absorbed dose to salivary glands instead of multiple time-point acquisitions.

177 Lu-PSMA-617 Therapy in a Case of Metastatic Castration-Resistant Prostate Cancer

ABSTRACT

We report a 65-year-old man with metastatic castration-resistant prostate cancer who was treated with 2 cycles of 177 Lu-PSMA-617 therapy. PET/CT imaging of 68 Ga-PSMA-11 revealed a complete metabolic response (PERCIST1.0) after therapy. The prostate-specific antigen concentration drastically decreased (97.7% down).

PSMA Radioligand Therapy in Prostate Cancer: Where Are We and Where Are We Heading?

ABSTRACT

Diagnosis and treatment of prostate cancer are complex and very challenging, being a major health care burden. The efficacy of radioligand therapy with prostate-specific membrane antigen agents has been proven beneficial in certain clinical indications. In this review, we describe management of prostate cancer patients according to current guidelines, especially focusing on the available clinical evidence for prostate-specific membrane antigen radioligand therapy.

Is There a Role of Interim PSMA PET in Chemotherapy of Prostate Cancer?

While RECIST 1.1 is well established in radiological response assessment, it is of limited use in prostate cancer (PCa) considering that the disease is often seen only as sclerotic bone changes on conventional imaging. Therefore, a molecular imaging-based response assessment including bone scans has been proposed and used in clinical trials, however, due to the flare phenomenon on bone scans this assessment leads to substantial delays in the detection of progression. Indeed, a robust and reliable imaging tool to assess response to chemotherapy in PCa is still warranted. Whether Positron Emission Tomography (PET) targeting the Prostate-Specific Membrane Antigen (PSMA) could achieve this, is still controversial. In this review, we summarized the available data on cytotoxic agents and their impact on PSMA expression, as well as the available data on PSMA PET imaging for response assessment.

[177Lu]Lu-PSMA-617 Versus Docetaxel in Chemotherapy-Naïve Metastatic Castration-Resistant Prostate Cancer: Final Survival Analysis of a Phase 2 Randomized, Controlled Trial

The prostate-specific membrane antigen (PSMA) inhibitor [177Lu]Lu-PSMA-617 has been previously demonstrated to be noninferior to docetaxel in achieving a biochemical response in chemotherapy-naïve metastatic castration-resistant prostate cancer patients. Here, we report the final analysis of overall survival (OS) for a phase 2 randomized, controlled trial. Methods: Forty chemotherapy-naïve, PSMA-positive metastatic castration-resistant prostate cancer patients were randomly assigned to [177Lu]Lu-PSMA-617 (n = 20) or docetaxel (n = 20). Thirty-five patients received treatment per the protocol. Survival analysis was done using Kaplan-Meier curves and the Cox regression model. Results: The mean follow-up duration was 33.4 mo. In intention-to-treat analysis, the median OS for the [177Lu]Lu-PSMA-617 and docetaxel arms was 15.0 mo (95% CI, 9.5-20.5 mo) and 15.0 mo (95% CI, 8.1-21.9 mo), respectively (P = 0.905). In per-protocol analysis, the median OS was 19.0 mo (95% CI, 12.3-25.7 mo) versus 15.0 mo (95% CI, 8.1-21.9 mo), respectively (P = 0.712). No significant difference in OS was observed between the 2 arms across the analyzed subgroups. Conclusion: Long-term outcomes with [177Lu]Lu-PSMA-617 administered earlier in the prechemotherapy setting are comparable to those with docetaxel.

PSMA-targeted radioligand therapy in prostate cancer: current status and future prospects

INTRODUCTION

The prostate-specific membrane antigen (PSMA) targeted radioligand therapy (PRLT) for the treatment of metastatic castration-resistant prostate cancer (mCRPC) patients has generated significant interest among the oncologic community, with several publications documenting good response rates and survival benefits with low toxicity profiles.

AREAS COVERED

Indications, patient preparation, dose administration, post-treatment imaging, dosimetry, and side effect profiles of 177Lu-PSMA-617 are discussed in this article. We also discuss results from prospective studies, major retrospective studies, meta-analyses, clinical trials, and mentioned major ongoing clinical trials on PRLT. We have also portrayed our own experiences and future perspectives on PRLT.

EXPERT OPINION

For PRLT, PSMA-617 and PSMA-I&T molecules have revolutionized the theranostic approach in the management of advanced prostate cancer, with solid backing from several published articles showing favorable outcomes and an excellent safety profile of 177Lu-PSMA-617. Improvement in quality of life and survival was seen in the majority of mCRPC patients after 177Lu-PSMA-617 PRLT. Patients with good performance status, asymptomatic, only lymph node metastases, high PSMA expressing lesions, and no discordant FDG avid lesions have a longer survival after 177Lu-PSMA-617 PRLT than patients with poor performance status, symptomatic, hepatic, brain, and skeletal metastases, discordant PSMA, and FDG-avid lesions. Docetaxel and cabazitaxel are approved treatments for mCRPC patients. 177Lu-PSMA-617 is approved as a third-line systemic treatment for mCRPC patients with failure to respond to androgen receptor pathway inhibitors and docetaxel therapy. PRLT is a safe and effective alternative to cabazitaxel (third-line systemic treatment), but it has a higher cost. 177Lu-PSMA-617 could be a more efficient therapeutic option for mCRPC patients as first-line or combined therapy, and it may be a useful therapeutic option for the treatment of metastatic hormone-sensitive prostate cancer (mHSPC) patients. Several clinical studies and clinical trials on PRLT are currently underway. In the future, the results of these trials will be helpful in evolving treatment strategies for prostate cancer patients.

Joint EANM/SNMMI procedure guideline for the use of 177Lu-labeled PSMA-targeted radioligand-therapy (177Lu-PSMA-RLT)

Prostate-specific membrane antigen (PSMA) is expressed by the majority of clinically significant prostate adenocarcinomas, and patients with target-positive disease can easily be identified by PSMA PET imaging. Promising results with PSMA-targeted radiopharmaceutical therapy have already been obtained in early-phase studies using various combinations of targeting molecules and radiolabels. Definitive evidence of the safety and efficacy of [177Lu]Lu-PSMA-617 in combination with standard-of-care has been demonstrated in patients with metastatic castration-resistant prostate cancer, whose disease had progressed after or during at least one taxane regimen and at least one novel androgen-axis drug. Preliminary data suggest that 177Lu-PSMA-radioligand therapy (RLT) also has high potential in additional clinical situations. Hence, the radiopharmaceuticals [177Lu]Lu-PSMA-617 and [177Lu]Lu-PSMA-I&T are currently being evaluated in ongoing phase 3 trials. The purpose of this guideline is to assist nuclear medicine personnel, to select patients with highest potential to benefit from 177Lu-PSMA-RLT, to perform the procedure in accordance with current best practice, and to prepare for possible side effects and their clinical management. We also provide expert advice, to identify those clinical situations which may justify the off-label use of [177Lu]Lu-PSMA-617 or other emerging ligands on an individual patient basis.

Lutetium-177 PSMA for the treatment of metastatic castrate resistant prostate cancer: a systematic review

INTRODUCTION

Metastatic castrate resistant prostate cancer (mCPRC) remains an aggressive form of prostate cancer that no longer responds to traditional hormonal treatment alone. Despite the advent of novel anti-androgen medications, many patients continue to progress, and as a result, there is a growing need for additional treatment options.

AREAS COVERED

Lutetium-177 (177Lu) - PSMA-617 has become one of the new frontline treatment options for refractory metastatic castrate resistant prostate cancer after the failure of novel anti-androgen therapy and chemotherapy. Lu-177 has been used in real-world prospective trials and is now becoming utilized in newer phase III clinical trials. Here, we present a comprehensive overview of the current literature, covering retrospective studies, prospective studies, and clinical trials that established Lutetium-177-PSMA-617 (177Lu-PSMA-617) for the treatment of mCRPC.

EXPERT OPINION

177Lu - PSMA-617 has been approved for treatment of mCRPC based on positive phase III studies. While this treatment is tolerable and effective, biomarkers are necessary to determine which patients will benefit. In the future, radioligand treatments will likely be utilized in earlier lines of therapy and potentially in combination with other prostate cancer treatments.

[177Lu]Lu-PSMA-Radioligand Therapy Efficacy Outcomes in Taxane-Naïve Versus Taxane-Treated Patients with Metastatic Castration-Resistant Prostate Cancer: A Systematic Review and Metaanalysis

Radioligand therapy (RLT) with ¹⁷⁷Lu-prostate-specific membrane antigen (PSMA) inhibitors ([¹⁷⁷Lu]Lu-PSMA) is currently approved for patients with metastatic castration-resistant prostate cancer (mCRPC) after progression with at least 1 taxane and 1 androgen-receptor-pathway inhibitor. However, the impact of prior chemotherapy on [¹⁷⁷Lu]Lu-PSMA-RLT outcomes is debatable, with various studies showing inconsistent results. This study was conducted to precisely evaluate the impact of prior taxane chemotherapy on response and survival outcomes in mCRPC patients after [¹⁷⁷Lu]Lu-PSMA-RLT. Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches in PubMed, Scopus, and Embase were made using relevant key words, and articles up to December 2022 were included. The endpoints included prostate-specific antigen (PSA) response rate (RR), progression-free survival, and overall survival (OS). Individual patient data were pooled when feasible. Univariate odds ratios (ORs) and hazard ratios (HRs) were extracted from the individual articles, and pooled estimates and 95% CIs were generated using metaanalysis. Results: Thirteen articles comprising 2,068 patients were included. In 6 articles (553 patients), taxane-naïve patients had significantly better odds of biochemical response after [¹⁷⁷Lu]Lu-PSMA-RLT (pooled OR, 1.82; 95% CI, 1.21-2.71). Individual patient data metaanalysis for PSA RRs in 3 articles revealed a significantly higher PSA RR in the taxane-naïve versus taxane-treated patients (57.1% vs. 39.5%; difference, 17.6%; 95% CI, 5.6%-28.9%). Further, taxane-naïve status was also a predictor of significantly better progression-free survival (5 articles; 1,027 patients; pooled HR, 0.60; 95% CI, 0.51-0.69) and OS (8 articles; 1,594 patients; pooled HR, 0.54; 95% CI, 0.43-0.68) after [¹⁷⁷Lu]Lu-PSMA-RLT. There was no evidence of publication bias. Conclusion: mCRPC patients with no prior taxanes had significantly better outcomes after [¹⁷⁷Lu]Lu-PSMA-RLT than did taxane-treated patients. Further trials evaluating [¹⁷⁷Lu]Lu-PSMA-RLT in the taxane-naïve setting are now required.

Treatments and challenges in advanced prostate cancer

PURPOSE OF REVIEW

This review is designed to highlight recent research examining treatment progress in advanced prostate cancer while identifying ongoing challenges to clinical outcomes.

RECENT FINDINGS

Recent randomized trials suggest an overall survival advantage to treating some men with newly identified metastatic prostate cancer with a "triplet" of androgen deprivation therapy, docetaxel, and an androgen receptor axis-targeted agent. Questions remain about which men are best served by these combinations. Additional treatment success is being identified with prostate-specific membrane antigen positron emission tomography (PSMA)-radiopharmaceuticals, combinations involving targeted therapies, and novel manipulations of the androgen receptor axis. Challenges remain in selecting between available therapies, harnessing immune therapies, and treating tumors with emergent neuroendocrine differentiation.

SUMMARY

An expanding number of therapeutics are becoming available for men with advanced prostate cancer improving outcomes but at the same time making treatment selection more demanding. Ongoing research will be required to continue to hone treatment paradigms.

Case Report: Long-term complete response to PSMA-targeted radioligand therapy and abiraterone in a metastatic prostate cancer patient

Despite decades of research and clinical trials, metastatic castration-resistant prostate cancer (mCRPC) remains incurable and typically fatal. Current treatments may provide modest increases in progression-free survival but can come with significant adverse effects and are disaggregated from the diagnostic imaging needed to fully assess the spread of metastatic disease. A theranostic approach, using radiolabeled ligands that target the cell surface protein PSMA, simplifies the visualization and disease treatment process by enabling both to use similar agents. Here, we describe an exemplary case wherein a gentleman in his 70s with mCRPC on diagnosis was treated with 177Lu-PSMA-617 and abiraterone, and remains disease-free to date, over five years later.

Safety and Therapeutic Optimization of Lutetium-177 Based Radiopharmaceuticals

Peptide receptor radionuclide therapy (PRRT) using Lutetium-177 (¹⁷⁷Lu) based radiopharmaceuticals has emerged as a therapeutic area in the field of nuclear medicine and oncology, allowing for personalized medicine. Since the first market authorization in 2018 of [¹⁷⁷Lu]Lu-DOTATATE (Lutathera®) targeting somatostatin receptor type 2 in the treatment of gastroenteropancreatic neuroendocrine tumors, intensive research has led to transfer innovative ¹⁷⁷Lu containing pharmaceuticals to the clinic. Recently, a second market authorization in the field was obtained for [¹⁷⁷Lu]Lu-PSMA-617 (Pluvicto®) in the treatment of prostate cancer. The efficacy of ¹⁷⁷Lu radiopharmaceuticals are now quite well-reported and data on the safety and management of patients are needed. This review will focus on several clinically tested and reported tailored approaches to enhance the risk-benefit trade-off of radioligand therapy. The aim is to help clinicians and nuclear medicine staff set up safe and optimized procedures using the approved ¹⁷⁷Lu based radiopharmaceuticals.

Treatment of Advanced Metastatic Prostate Cancer Using Molecular-Targeted Therapy: Radioligand Lutetium-177 Prostate-Specific Membrane Antigen

This study investigates the predicting factors of the biochemical response and survival of patients with advanced metastatic prostate cancer who underwent therapy with radioligand lutetium-177 (¹⁷⁷Lu)-prostate-specific membrane antigen (PSMA), often referred to as [¹⁷⁷Lu]Lu-PSMA. This study is a review of the previous literature. This study included articles published in the last 10 years in the English language. According to the literature review, treatment with [¹⁷⁷Lu]Lu-PSMA has a positive impact on prostate-specific antigen (PSA) within the first cycle and a negative impact on lymph node metastasis. There is a plausible positive impact on PSA after multiple cycles and performance status and a negative impact on visceral metastasis. In conclusion, the reviews show that treatment with [¹⁷⁷Lu]Lu-PSMA in patients with castration-resistant prostate cancer is beneficial in reducing PSA and metastasis.

Genomic characterization of metastatic castration-resistant prostate cancer patients undergoing PSMA radioligand therapy: A single-center experience

BACKGROUND

Genomic defects in DNA-damage repair (DDR) mechanisms have been proposed to affect the radiosensitivity of prostate cancers. In this study, we intended to evaluate the prevalence of genetic alterations in a cohort of metastatic castration-resistant prostate cancer (mCRPC) patients undergoing radioligand therapy (RLT) with prostate-specific membrane antigen (PSMA)-inhibitors as well as the impact of such mutations on treatment outcomes.

METHODS

Data of consecutive mCRPC patients from 2017 to 2021 who were treated with PSMA-RLT and underwent next-generation sequencing (NGS) were collected and analyzed for response and survival outcomes.

RESULTS

In 95 patients of mCRPC treated with PSMA-RLT, 15 patients (median age: 66 years, range: 50-73 years; [¹⁷⁷ Lu]Lu-PSMA-617, n = 12; [²²⁵ Ac]Ac-PSMA-617, n = 3) underwent NGS. The median progression-free survival (PFS) of this cohort was 3 months (95% confidence interval: 1.6-4.4 months). On NGS, 21 genetic alterations were reported in 10/15 (67%) patients, of which 13 were DDR-associated alterations involving the genes: ATM (n = 3), BRCA2 (n = 3), TP53 (n = 2), PTEN (n = 2), FANCD2 (n = 1), FANCM (n = 1), and NBN (n = 1). Overall, 5/15 (33%) patients harbored six pathogenic variants (BRCA2, n = 2; ATM, n = 1; TP53, n = 1; PTEN, n = 2). No significant difference was noted for the biochemical response, radiological response, PFS, and overall survival between the patients with and without genetic alterations.

CONCLUSIONS

Patients of mCRPC undergoing PSMA-RLT were frequently seen to harbor DDR-associated aberrations, albeit with no significant impact on treatment outcomes. Large prospective trials comparing PSMA-RLT-related outcomes in DDR-deficient and -proficient patients are required to bring out the differences, if any, in a more observable manner.

Progression in immunotherapy for advanced prostate cancer

Prostate cancer is one of the most common malignant cancers of the male genitourinary system and has high morbidity and mortality. Currently, treatment modalities for localized prostate cancer focus mainly on radical prostatectomy or radical radiation therapy. Some patients still experience disease recurrence or progression after these treatments, while others are already at an advanced stage or have metastases at the time of diagnosis. With the continuous development and progress of medicine in recent years, immunotherapy has become a revolutionary cancer treatment, and has achieved remarkable accomplishments in the treatment of hematologic malignancies. A variety of immunotherapies have also appeared in the field of advanced prostate cancer treatment, including therapeutic vaccines and immune checkpoint therapies. Despite the discrepancy between the results of some immunotherapy studies, immunotherapy for prostate cancer has shown some initial success, especially in combination immunotherapies. Currently, immunotherapy is mainly used in advanced prostate cancer, especially in patients with metastatic castration-resistant prostate cancer. However, with the development of more clinical trials of immunotherapy, more evidence will be provided supporting the rational application of immunotherapy in the future.

Current Status of PSMA-Targeted Radioligand Therapy in the Era of Radiopharmaceutical Therapy Acquiring Marketing Authorization

Prostate-specific membrane antigen (PSMA) is highly expressed in PCa, which gradually increases in high-grade tumors, metastatic tumors, and tumors nonresponsive to androgen deprivation therapy. PSMA has been a topic of interest during the past decade for both diagnostic and therapeutic targets. Radioligand therapy (RLT) utilizes the delivery of radioactive nuclides to tumors and tumor-associated targets, and it has shown better efficacy with minimal toxicity compared to other systemic cancer therapies. Nuclear medicine has faced a new turning point claiming theranosis as the core of academic identity, since new RLTs have been introduced to clinics through the official new drug development processes for approval from the Food and Drug Administration (FDA) or European Medical Agency. Recently, PSMA targeting RLT was approved by the US FDA in March 2022. This review introduces PSMA RLT focusing on ongoing clinical trials to enhance our understanding of nuclear medicine theranosis and strive for the development of new radiopharmaceuticals.

[177Lu]Lu-PSMA-617 (PluvictoTM): The First FDA-Approved Radiotherapeutical for Treatment of Prostate Cancer

In March 2022, [¹⁷⁷Lu]Lu-PSMA-617 (Pluvicto^TM) was approved by the FDA for the treatment of prostate cancer patients. Until now, the approval has been limited to patients with PSMA-positive metastatic castration-resistant prostate cancer who have previously received other therapy options (such as inhibition of the androgen receptor pathway and taxane-based chemotherapy). [¹⁷⁷Lu]Lu-PSMA-617, which combines a PSMA-specific peptidomimetic with a therapeutical radionuclide, is used in a radioligand therapy that selectively delivers ionizing radiation to tumor cells, causing their death, while sparing the surrounding healthy tissue. In numerous clinical trials, the efficacy of [¹⁷⁷Lu]Lu-PSMA-617 was demonstrated.

Systemic Therapy Update on 177Lutetium-PSMA-617 for Metastatic Castration-Resistant Prostate Cancer: ASCO Rapid Recommendation

ASCO Rapid Recommendations Updates highlight revisions to select ASCO guideline recommendations as a response to the emergence of new and practice-changing data. The rapid updates are supported by an evidence review and follow the guideline development processes outlined in the ASCO Guideline Methodology Manual. The goal of these articles is to disseminate updated recommendations, in a timely manner, to better inform health practitioners and the public on the best available cancer care options.

Lutetium Lu 177 Vipivotide Tetraxetan: First Approval

Lutetium Lu 177 vipivotide tetraxetan (PLUVICTO™, formerly known as ¹⁷⁷Lu-PSMA-617) is a radioligand therapeutic agent that is being developed by Advanced Accelerator Applications (a subsidiary of Novartis) for the treatment of prostate-specific membrane antigen (PSMA)-expressing metastatic prostate cancer. The active part of the radiopharmaceutical is lutetium-177, which is linked to a ligand that binds to prostate-specific membrane antigen (PSMA), a transmembrane enzyme overexpressed in primary and metastatic prostate cancers. Based on efficacy results from the phase 3 VISION trial, lutetium Lu 177 vipivotide tetraxetan was approved in the USA on 23 March 2022 for the treatment of adult patients with PSMA-positive metastatic castration-resistant prostate cancer (mCRPC) who have been treated with androgen receptor (AR) pathway inhibition and taxane-based chemotherapy. Regulatory review in the EU and other countries is underway. This article summarizes the milestones in the development of Lutetium Lu 177 vipivotide tetraxetan leading to this first approval as a therapeutic radioligand for mCRPC.

Theranostic Options for Radioiodine-Refractory Differentiated Thyroid Carcinoma: Recent Advances, Challenges, and Road Ahead

Radioiodine-refractory differentiated thyroid cancer (RAIR-DTC), though uncommon, presents a considerable therapeutic challenge with poor long-term outcomes. Currently, tyrosine kinase inhibitors are the mainstay of treatment for advanced RAIR-DTC patients. However, these agents are associated with a multitude of adverse events with resultant deterioration in the quality-of-life of the patients. Targeted theranostic approaches with radiolabelled integrin binders and fibroblast activation protein- (FAP)-inhibitors seem to have a promising role in the management of such patients. This mini-review focuses on these novel theranostic strategies in RAIR-DTC, with emphasis on recent advances, existing challenges, and future directions.