Medical Oncologist
Drug deep dive: Enhertu
Trastuzumab Deruxtecan Success Rate: — An Honest Look at the Numbers
When a doctor prescribes trastuzumab deruxtecan, the first question many families ask is: how often does it work? The answer depends on which cancer you have, how far it has advanced, and which clinical trial your situation matches.
Medically reviewed by Dr. C. Raghavendra Reddy, Medical Oncologist, MBBS (Gold Medal) · DNB · DM (Medical Oncology, Gold Medal) · Last reviewed August 2026
- Numbers vary by cancer type — Trial results in breast cancer are not the same as results in gastric or lung cancer. Your oncologist will tell you which data applies to you.
- A median is not a prediction — Half of patients in a trial do better than the median, and half do worse. It describes a group, not what will happen to you.
- Response rate is not survival — A tumour shrinking on scans is meaningful, but it is not the same as long-term disease control. Both are reported separately in the trials.
- The evidence is still maturing — Trastuzumab deruxtecan has been approved in several cancers at different times. The data in newer indications has less long-term follow-up.
17+
Cancer Specialists
on Panel
on Panel
96.9%
Breast Cancer
Survival Rate*
Survival Rate*
15,000+
Patients
Treated
Treated
4.8★
Google Rating
(800+ reviews)
(800+ reviews)
Trastuzumab deruxtecan's success rate depends on your cancer type and treatment line — there is no single figure. ASCO and ESMO evidence shows meaningful improvements in progression-free survival across approved settings. What a median means for you specifically is a question your oncologist can answer from your own results.
Why is there no single success rate for this drug?
The answer depends on which cancer you have and where you are in your treatment. A trial in HER2-positive breast cancer shows different results from one in HER2-low breast cancer, gastric cancer, or HER2-mutated lung cancer.
Even within one cancer type, the numbers shift depending on whether trastuzumab deruxtecan is being used as a first, second, or later treatment. Each approval was earned in a specific setting, and the evidence only applies to that setting.
Your oncologist is not withholding a number. They are telling you the number that actually applies to your situation — which is the only one that matters.
What do these terms mean?
- Objective response rate (ORR)
- The proportion of patients in a trial whose tumour shrank to a measurable degree on scans. A response shows the drug is having an effect, but it does not mean the cancer has gone.
- Median progression-free survival (PFS)
- The midpoint of how long trial participants were free from their cancer growing again or from death. Half the group reached this point without progression — half progressed before it.
- Median overall survival (OS)
- The midpoint of how long participants lived from the start of treatment. Half lived longer than this figure; half did not reach it. It is a midpoint, not a ceiling or a prediction.
- Complete response
- No detectable cancer on imaging after treatment. A meaningful result, but it does not always mean the cancer is permanently gone.
- Partial response
- The tumour shrank significantly — measured to a defined threshold in the trial protocol — though some cancer remains visible on scans.
- Disease control rate
- The proportion of patients whose cancer either responded or remained stable. Stable disease without shrinkage can still be a useful outcome for some patients.
Does this drug work better in some cancers than in others?
Yes. NCCN, ASCO, and ESMO guidance reflects different evidence bases for different cancer types. Results in second-line HER2-positive breast cancer, where the largest trials were conducted, differ from results in HER2-low breast cancer, HER2-mutated lung cancer, and gastric cancer.
Newer indications — where the approval came more recently — have less long-term follow-up data. That does not make the approval unjustified. It means the evidence is still maturing, and that is worth knowing.
Ask your oncologist to name the trial and explain what it found for your specific cancer. That is the evidence you are actually working with.
Meet the Specialists
17+ senior cancer specialists. One panel for your case.
Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Surgical Oncologist
Dr. Muralidhar Muddusetty
MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)
Surgical Oncologist
Surgical Oncologist
Surgical Oncologist
Dr. Vinay Mamidala
MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)
Surgical Oncologist
Radiation Oncologist
Radiation Oncologist
Radiation Oncologist
Hematologist
Interventional Radiologist
Dr. Mohammed Imran
Surgical Oncologist
Dr. Vajja Sandeep Kumar
MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology
Surgical Oncologist
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
You do not have to work this out alone
A 45-minute consultation with a specialist who treats this every week.
How do you make sense of a clinical trial result?
Find out which trial applies to you
Ask your oncologist which specific trial trastuzumab deruxtecan was approved on for your cancer. The trial name, patient profile it enrolled, and setting tell you whether the result is relevant to your situation.
Look at what it was compared to
A response rate or survival figure means more when you know what the comparator arm received. Results in the approved trials were measured against the previous standard of care, and the benefit is the gap between the two arms.
Understand the median correctly
A median progression-free survival tells you the midpoint of a trial group. Half the participants were free from progression beyond that point, and half had progressed before it. You may be in either half — the trial cannot tell you which.
Ask about the range of responses
A wide range of individual results around the median tells you there is meaningful variation between patients. A narrow range suggests the drug behaves more consistently. Ask your oncologist what the spread looked like in the relevant trial.
Separate response from survival
Response rate and survival are different measurements. A high proportion of tumours shrinking does not automatically mean a long survival benefit. Ask what both figures showed — separately — for your specific setting.
What do the numbers tell you about your own case?
A trial median describes the midpoint of a large group of people with different tumours, different fitness levels, and different treatment histories. You are not a group average.
Your response will depend on how your specific tumour behaves, your general health, the treatments you have already received, and factors no trial controls for individually.
This is not a reason to distrust the data — trials are the best evidence we have. It is a reason not to let a median become a sentence in either direction. Bring any fear or hope the numbers have raised into your next appointment. Your oncologist can put both in the context of your actual scans and results.
Questions families ask most
What should I ask my oncologist about these numbers?
Ask three specific things: which clinical trial the drug was approved on for your cancer, what the response rate and progression-free survival showed in that trial, and what the comparator arm received. Those three pieces give you a complete picture of what the evidence actually showed, not just a headline figure without context. Write the answers down — these conversations are hard to remember when you are under pressure.
Does a high response rate mean the drug will work for a long time?
Not necessarily. Response rate — the proportion of patients whose tumour shrank — is measured at a point in time and does not capture how long that response will last. Progression-free survival is the separate figure that addresses durability, and the two do not always move together. A drug can produce a high response rate and a shorter-than-hoped progression-free survival. Your oncologist can explain both figures for the specific trial that applies to your cancer.
What if I am doing better than the numbers suggested I might?
Medians are not ceilings, and a strong ongoing response is not a reason for anxiety. Some patients in the trials that led to trastuzumab deruxtecan's approvals had responses that lasted well beyond the median. There is no statistical reason to expect your response to stop at any particular point. Attend your scheduled scans, report new symptoms promptly, and let your actual results — not a number from a trial — guide the conversation with your oncologist.
What if the cancer is not responding?
Your oncologist will discuss the options based on your cancer type, what other treatments you have already received, and your current fitness. Not every cancer responds to trastuzumab deruxtecan, and knowing that early — rather than continuing a treatment that is not helping — is useful information. Trials of this drug in new settings and in combination with other agents are ongoing. NCCN and ESMO guidance is updated as new evidence emerges, and your team will be aware of what applies to you.
How does this drug compare to what I was offered before?
The trials that earned trastuzumab deruxtecan its approvals compared it against the previous standard of care in each setting. ASCO and ESMO reviewed that evidence and reflected it in their guidance. The comparison that matters for you is between this drug and whatever the realistic alternative would be for your specific cancer and line of treatment. Your oncologist can explain that comparison directly — a clear answer to it is reasonable to expect.
Are these trial numbers relevant to patients in India?
The global trials that earned trastuzumab deruxtecan its approvals enrolled patients across multiple countries, and Indian patients were included in some of them. That said, response rates and survival outcomes can differ between populations due to differences in tumour biology, genetic background, and how advanced the disease is when treatment begins. Ask your oncologist whether there is India-specific or Asian-cohort data for your cancer type, and discuss what the global evidence means in your specific context.
Explore 75 more Breast Cancer Targeted Medicines topics
Drug Deep Dive: Trastuzumab Deruxtecan (Enhertu)
- Diet and Nutrition While on Trastuzumab Deruxtecan
- Drug, Food and Supplement Interactions With Trastuzumab Deruxtecan
- Enhertu Myths: 'It's Just Stronger Herceptin' and Cost Misconceptions
- Enhertu in Breast, Gastric and Lung Cancer: One Drug, Three Diseases
- Fertility, Pregnancy and Contraception on Trastuzumab Deruxtecan
- HER2-Low Breast Cancer: How Enhertu Created an Entirely New Patient Group
- How Does Trastuzumab Deruxtecan Work? The HER2-Directed Antibody-Drug Conjugate Explained
- How Long Does Trastuzumab Deruxtecan Take to Work?
- How Long Will You Stay on Trastuzumab Deruxtecan?
- Interstitial Lung Disease on Enhertu: The Side Effect That Needs Immediate Action
- Low Blood Counts, Hair Loss and Heart Monitoring on Enhertu
- Nausea and Vomiting on Trastuzumab Deruxtecan: Managing a High-Risk ADC
- Tests and Monitoring While You Are on Trastuzumab Deruxtecan
- Trastuzumab Deruxtecan (Enhertu): The Complete Patient Guide
- Trastuzumab Deruxtecan Infusion Day: Premedication, Duration and What to Expect
- Trastuzumab Deruxtecan Price in India: Innovator, Biosimilar and Cost Per Cycle
- Trastuzumab Deruxtecan Side Effects: The Complete List and Timeline
- Trastuzumab Deruxtecan Success Rate and Survival: An Honest Look at the Numbers
- Trastuzumab Deruxtecan in Elderly Patients and Those With Other Illnesses
- Trastuzumab Deruxtecan vs T-DM1 and Trastuzumab: How ADCs Differ
- When Trastuzumab Deruxtecan Stops Working: Resistance and What Comes Next
- Where Trastuzumab Deruxtecan Fits Alongside Chemotherapy and Hormone Therapy
- Who Is Eligible for Trastuzumab Deruxtecan? HER2-Positive and HER2-Low Breast, Gastric and Lung Cancer
- Will Insurance or a Government Scheme Pay for Trastuzumab Deruxtecan?
- Work, Travel and Daily Life on Trastuzumab Deruxtecan
Drug Deep Dive: Palbociclib (Ibrance)
- Diet and Nutrition While on Palbociclib
- Drug, Food and Supplement Interactions With Palbociclib
- Fatigue on Palbociclib: Why It Happens and What Genuinely Helps
- Fertility, Pregnancy and Contraception on Palbociclib
- How Does Palbociclib Work? The CDK4/6 Inhibitor Explained
- How Long Does Palbociclib Take to Work?
- How Long Will You Stay on Palbociclib?
- Low White Cell Count on Palbociclib: Expected, and Rarely Dangerous
- Mouth Sores and Infection Risk on Palbociclib
- Palbociclib (Ibrance, Palbace): The Complete Patient Guide
- Palbociclib Myths: Low Counts, Hair Loss and Stopping Early
- Palbociclib Price in India: Brand, Generic and Monthly Cost
- Palbociclib Side Effects: The Complete List and Timeline
- Palbociclib Success Rate and Survival: An Honest Look at the Numbers
- Palbociclib With Letrozole or Fulvestrant: Understanding Your Combination
- Palbociclib in Early Breast Cancer: Why It Is Not Given After Surgery
- Palbociclib in Elderly Patients and Those With Other Illnesses
- Palbociclib vs Ribociclib vs Abemaciclib: Which CDK4/6 Inhibitor?
- Taking Palbociclib: Food, Timing and What to Do If You Miss a Dose
- Tests and Monitoring While You Are on Palbociclib
- The 21-Days-On, 7-Days-Off Palbociclib Cycle Explained
- When Palbociclib Stops Working: Resistance and What Comes Next
- Who Is Eligible for Palbociclib? Hormone-Receptor-Positive, HER2-Negative Breast Cancer
- Will Insurance or a Government Scheme Pay for Palbociclib?
- Work, Travel and Daily Life on Palbociclib
Drug Deep Dive: Trastuzumab (Herceptin)
- Adjuvant Trastuzumab: Why Exactly 12 Months After Surgery?
- Diet and Nutrition While on Trastuzumab
- Drug, Food and Supplement Interactions With Trastuzumab
- Fatigue, Chills and Flu-Like Symptoms After a Trastuzumab Infusion
- Fertility, Pregnancy and Contraception on Trastuzumab
- Heart Function and Trastuzumab: Understanding Your ECHO Reports
- Herceptin vs Biosimilar Trastuzumab: Are They Really the Same?
- How Does Trastuzumab Work? The Anti-HER2 Monoclonal Antibody Explained
- How Long Does Trastuzumab Take to Work?
- How Long Will You Stay on Trastuzumab?
- Subcutaneous Trastuzumab vs IV Infusion: Which Suits You Better?
- Tests and Monitoring While You Are on Trastuzumab
- Trastuzumab (Herceptin and biosimilars): The Complete Patient Guide
- Trastuzumab Infusion Day: Premedication, Duration and What to Expect
- Trastuzumab Infusion Reactions: What Happens and How They're Managed
- Trastuzumab Myths: 'It's Chemotherapy' and Other Misunderstandings
- Trastuzumab Price in India: Innovator, Biosimilar and Cost Per Cycle
- Trastuzumab Side Effects: The Complete List and Timeline
- Trastuzumab Success Rate and Survival: An Honest Look at the Numbers
- Trastuzumab With Pertuzumab, Chemotherapy and Hormone Therapy
- Trastuzumab in Elderly Patients and Those With Other Illnesses
- When Trastuzumab Stops Working: Resistance and What Comes Next
- Who Is Eligible for Trastuzumab? HER2-Positive Breast and Gastric Cancer
- Will Insurance or a Government Scheme Pay for Trastuzumab?
- Work, Travel and Daily Life on Trastuzumab
Next step
Still not sure what applies to you?
Send your reports across and a senior medical oncologist will go through what they mean, what is known, and what the options actually are.
Common questions
Frequently asked questions
What is a good response rate for trastuzumab deruxtecan?
Response rate depends entirely on which cancer and which line of treatment is being discussed. ASCO and ESMO guidance covers each approved indication separately, and the evidence base differs between them. A rate that looks modest can still represent a meaningful benefit over the alternative in that setting. The right question to ask your oncologist is not whether the rate is high in the abstract, but whether it is better than what the realistic alternative would offer for your specific cancer and stage.
How long does trastuzumab deruxtecan work before the cancer progresses?
The duration of response varies between patients and between cancer types. The published figures from clinical trials describe the midpoint of a group, not a limit on how long any individual can respond. Some patients have durable responses well beyond the median, and some progress earlier. Your oncologist can tell you what the specific trial data showed for your cancer and help you interpret what your current scans are showing in that context.
What happens when trastuzumab deruxtecan stops working?
If the cancer progresses, your oncologist will reassess your options based on your cancer type, what treatments you have already had, and your current fitness. Research into what to use after trastuzumab deruxtecan is an active area, and options are being studied and approved on an ongoing basis. Progression on one treatment does not mean there are no further options, and your team will review what the current evidence supports for your next step.
Is trastuzumab deruxtecan better than chemotherapy?
For the specific settings it is approved in, ASCO and ESMO evidence supports trastuzumab deruxtecan over the previous standard of care, which was often chemotherapy or another antibody-drug conjugate. That evidence applies to those approved settings only. Outside them, or at different stages, the comparison changes. Your oncologist's recommendation is based on the evidence for your specific cancer, stage, and treatment history — and asking them to explain the comparison directly is a reasonable request.
How will I know if trastuzumab deruxtecan is working for me?
Response is assessed on imaging — typically a CT scan at intervals your oncologist specifies — and sometimes through blood markers depending on your cancer type. The scan after the first few cycles gives an early indication, though a single result is not always definitive. You will also be asked about symptoms at each visit. If the cancer is responding, scans will typically show the tumour shrinking or remaining stable. Ask your oncologist what the scan schedule is and what each result will tell you.
Is trastuzumab deruxtecan available at CION?
Trastuzumab deruxtecan is administered as day care at CION centres across Telangana and Andhra Pradesh. Response-assessment scans such as PET-CT are coordinated through partner imaging centres. CION does not provide CAR-T or cell therapy. Ask your oncologist at your next appointment whether this drug is the right option for your cancer and stage, and what the administration schedule at your nearest centre would look like.