Caitlyn Bos, Arkojyoti Das and Rituraj Sen coauthored this article.

Key takeaways:

• Early pharma product launch success signals come from breadth, return writing rate and depth, which show whether launch trajectory is building by month six.
• The strongest launch performance benchmarks follow the 3-5-3 rule, with 30% breadth, 50% return writing rate and 30% depth by month six.
• Launch teams can diagnose risk by identifying which prescribing hallmark is weak, then focusing intervention on awareness, access, targeting, experience or education barriers.

Six months into launch, leaders should have enough evidence to decide whether adoption is building or whether the team needs to intervene while the trajectory can still change. That decision depends on the same launch commitment principle ZS has seen across broader launch research: successful teams build a system to detect adoption breakdowns early, resolve barriers quickly and maintain execution velocity under real-world conditions.

A ZS analysis of 18 specialty launches identifies three prescribing hallmarks that make those breakdowns visible in the first six months: breadth, return writing rate and depth. Launches that met all three thresholds at the six-month mark were approximately nine times more likely to succeed than those that did not.

The value of these signals is not simply predictive. Each one points to a different launch-room decision, from where to push awareness and access to where to improve prescriber experience and build confidence through education and patient identification.

Why pharma launch trajectory is hard to read early

The question sounds simple: Are we on a path to fulfill this asset’s potential? In practice, the answer is deceptively hard to know early enough to change course. Consider launches that missed forecast in the first quarter and needed to understand what the miss meant for trajectory. Those launches tend to fall into three patterns:

• A highly anticipated first-in-class launch with slower-than-expected early adoption
• A well-resourced launch struggling to displace a market leader
• A launch with early traction but unclear momentum

Despite different starting points, these launches face the same problem. Leaders often struggle to know early enough whether trajectory is building or already behind. That uncertainty slows decisions at the moment they matter most and can lock in underperformance before teams act. Leaders need early signals that make trajectory visible while there is still time to act. Breadth, return writing rate and depth do that and determine whether to stay the course or intervene.

The 3 prescribing hallmarks that show whether launch trajectory is on track

1. Breadth of prescribing. Are 30% of priority targets prescribing by month six?

Breadth measures the percentage of priority target physicians who have written at least one prescription. Separation in breadth of prescribing between successful and unsuccessful launches is visible as early as month three and widens through month six.

FIGURE 1: Breadth of prescribing by launch cohort shows whether leaders need to adjust targeting, awareness or access

Note: Priority targets as defined represent what is typically the top one-third of the overall target list.

2. Return writing rate. Are 50% of monthly active writers returning by month six?

Return writing rate measures the percentage of physicians prescribing in a given month who have also prescribed in a prior month. The metric shows whether physicians who try the product come back to use it again, turning initial trial into a stable base of experienced prescribers. That base matters because return writers can help influence peers, a signal that often drives broader adoption in specialist communities.

FIGURE 2: Return writing rate by launch cohort shows whether leaders need to improve the prescriber experience

3. Depth of prescribing. Are 30% of writers reaching three or more patients by month six?

Depth measures the percentage of writers who have prescribed to at least three unique patients. Reaching a third patient signals that physicians are moving beyond initial trial and building enough experience to form a clear point of view.

FIGURE 3: Depth of prescribing by launch cohort shows whether leaders need to build confidence through education and patient identification

Note: The number of eligible patients per physician is relatively consistent across the markets analyzed. Significant deviations may require adjusting this threshold.

How prescribing hallmarks show whether adoption is becoming durable

The three hallmarks matter most when read together because they show whether adoption is moving from trial to repeat use to durable confidence. Each signal adds a different diagnostic layer:

• Breadth indicates whether enough targets have tried the product to create early momentum
• Return writing rate shows whether trial is converting into repeat prescribers, who become more likely to advocate to peers
• Depth reflects whether prescribers are building enough experience to sustain adoption and build clinical confidence

Their predictive weight also shifts over time:

• Months one to three: breadth carries the most weight
• Months four to five: return writing rate adds to breadth as a key signal
• Months five to six: depth adds further, indicating whether adoption is becoming durable

How the 3-5-3 rule performed across 18 pharma launches

By month six, trajectory was clear enough to guide action. Launches that met all three thresholds were approximately nine times more likely to succeed than those that did not. The pattern also showed where leaders needed to look harder. Brand C was the exception. Infusion site capacity and a lack of established referral pathways among target specialists constrained early adoption despite underlying demand.

FIGURE 4: Performance against the three prescribing hallmarks shows where leaders should stay the course, diagnose constraints or intervene

When all three hallmarks are strong, the launch has built the foundation needed to sustain growth. When one or more are weak, the gap points to where intervention is needed:

• Low breadth suggests likely barriers in awareness, access or targeting.
• Low return writing rate indicates an experience issue, whether clinical, access-related or patient support, that needs to be diagnosed.
• Low depth suggests caution in patient selection, access challenges for certain patient types or gaps in education on appropriate patient identification.

Taken together, the hallmarks do more than describe performance. They help pinpoint where the launch is breaking down and where to act while there is still time to change the trajectory. Strong launch teams use them as the entry point into a continuous diagnostic loop by monitoring KPIs, identifying opportunities in real time, using underlying intel to identify root causes and convening cross-functional teams to course-correct. Adjusting in motion is how good launch teams run a launch room. The hallmarks give that process a shared language and a concrete trigger for action.

What launch teams need to decide by month six

Benchmarks for the three early hallmarks of launch trajectory are highly predictive of launch success. Launches that meet all three thresholds are approximately nine times more likely to succeed than those that don’t. Launch teams can use these metrics and associated benchmark values to gain early alignment on trajectory and adjust course while time remains. The next move is to identify the weakest signal, diagnose the commercial, access or experience barrier behind the gap and act before the trajectory hardens.